-
+ 68FBCBEBE57013E70F798EC673D6C554CF0B118F41A56BAF92D53686F8D24FDA670ED6DDA23C6CBAB630DFAF8CBF6D6A52A6815AC3680B24DAD99B1305DE6279
bitcoin/src/obj-shiva/.gitignore

(0 . 0)(1 . 2)
*
!.gitignore

-
+ 3D7A61B123D7D1724A079C211678DD85085E56F4C2229C46D9DF7A7257E83461E0F19237C90B58A17E977B19715651539317003A69FFFD06C3CC96D0EA54839B
bitcoin/src/shiva/BUILDING

(0 . 0)(1 . 139)
        Building TinyScheme
        -------------------

The included makefile includes logic for Linux, Solaris and Win32, and can
readily serve as an example for other OSes, especially Unixes. There are
a lot of compile-time flags in TinyScheme (preprocessor defines) that can trim
unwanted features. See next section. 'make all' and 'make clean' function as
expected.

Autoconfing TinyScheme was once proposed, but the distribution would not be
so small anymore. There are few platform dependencies in TinyScheme, and in
general compiles out of the box.

     Customizing
     -----------

     The following symbols are defined to default values in scheme.h.
     Use the -D flag of cc to set to either 1 or 0.

     STANDALONE
     Define this to produce a standalone interpreter.

     USE_MATH
     Includes math routines.

     USE_CHAR_CLASSIFIERS
     Includes character classifier procedures.

     USE_ASCII_NAMES
     Enable extended character notation based on ASCII names.

     USE_STRING_PORTS
     Enables string ports.

     USE_ERROR_HOOK
     To force system errors through user-defined error handling.
     (see "Error handling")

     USE_TRACING
     To enable use of TRACING.

     USE_COLON_HOOK
     Enable use of qualified identifiers. (see "Colon Qualifiers - Packages")
     Defining this as 0 has the rather drastic consequence that any code using
     packages will stop working, and will have to be modified. It should only
     be used if you *absolutely* need to use '::' in identifiers.

     USE_STRCASECMP
     Defines stricmp as strcasecmp, for Unix.

     STDIO_ADDS_CR
     Informs TinyScheme that stdio translates "\n" to "\r\n". For DOS/Windows.

     USE_DL
     Enables dynamically loaded routines. If you define this symbol, you
     should also include dynload.c in your compile.

     USE_PLIST
     Enables property lists (not Standard Scheme stuff). Off by default.
     
     USE_NO_FEATURES
     Shortcut to disable USE_MATH, USE_CHAR_CLASSIFIERS, USE_ASCII_NAMES,
     USE_STRING_PORTS, USE_ERROR_HOOK, USE_TRACING, USE_COLON_HOOK,
     USE_DL.

     USE_SCHEME_STACK
     Enables 'cons' stack (the alternative is a faster calling scheme, which 
     breaks continuations). Undefine it if you don't care about strict compatibility
     but you do care about faster execution.


     OS-X tip
     --------
     I don't have access to OS-X, but Brian Maher submitted the following tip:

[1] Download and install fink (I installed fink in
/usr/local/fink)
[2] Install the 'dlcompat' package using fink as such:
> fink install dlcompat
[3] Make the following changes to the
tinyscheme-1.32.tar.gz

diff -r tinyscheme-1.32/dynload.c
tinyscheme-1.32-new/dynload.c
24c24
< #define SUN_DL
---
> 
Only in tinyscheme-1.32-new/: dynload.o
Only in tinyscheme-1.32-new/: libtinyscheme.a Only in tinyscheme-1.32-new/: libtinyscheme.so diff -r tinyscheme-1.32/makefile tinyscheme-1.32-new/makefile
33,34c33,43
< LD = gcc
< LDFLAGS = -shared
---
> #LD = gcc
> #LDFLAGS = -shared
> #DEBUG=-g -Wno-char-subscripts -O
> #SYS_LIBS= -ldl
> #PLATFORM_FEATURES= -DSUN_DL=1
> 
> # Mac OS X
> CC = gcc
> CFLAGS = -I/usr/local/fink/include
> LD = gcc
> LDFLAGS = -L/usr/local/fink/lib
37c46
< PLATFORM_FEATURES= -DSUN_DL=1
---
> PLATFORM_FEATURES= -DSUN_DL=1 -DOSX
60c69
<       $(CC) -I. -c $(DEBUG) $(FEATURES)
$(DL_FLAGS) $<
---
>       $(CC) $(CFLAGS) -I. -c $(DEBUG)
$(FEATURES) $(DL_FLAGS) $<
66c75
<       $(CC) -o $@ $(DEBUG) $(OBJS) $(SYS_LIBS) 
---
>       $(CC) $(LDFLAGS) -o $@ $(DEBUG) $(OBJS)
$(SYS_LIBS)
Only in tinyscheme-1.32-new/: scheme
diff -r tinyscheme-1.32/scheme.c
tinyscheme-1.32-new/scheme.c
60,61c60,61
< #ifndef macintosh
< # include <malloc.h>
---
> #ifdef OSX
> /* Do nothing */
62a63,65
> # ifndef macintosh
> #  include <malloc.h>
> # else
77c80,81
< #endif /* macintosh */
---
> # endif /* macintosh */
> #endif /* !OSX */
Only in tinyscheme-1.32-new/: scheme.o

-
+ 038EC4FD302239A956B99C57D8481FD5A5942BE9776174845CED951D584E16D4330A01C410321225FC601BA2CD96F37A4BAAFC9C6A32E305BCE41DB63314C08B
bitcoin/src/shiva/CHANGES

(0 . 0)(1 . 326)
Change Log
----------

Version 1.41
    Bugs fixed:
        #3020389 - Added makefile section for Mac OS X  (SL)
        #3286135 - Fixed num_mod routine which caused errors in use of modulo
        #3290232 - Corrected version number shown on startup  (GM)
        #3394882 - Added missing #if in opdefines.h around get and put  (DC)
        #3395547 - Fix for the modulo procedure  (DC)
        #3400290 - Optimized append to make it an O(n) operation  (DC)
        #3493926 - Corrected flag used when building shared files on OSX (J)

    R5RS related changes:
        #2866196 - Parser does not handle delimiters correctly
        #3395548 - Add a decimal point to inexact numbers in atom2str  (DC)
        #3399331 - Make min/max return inexact when any argument is inexact
        #3399332 - Compatability fix for expt.
        #3399335 - Optional radix for string->number and number->string  (DC)
        #3400202 - Append with one argument should not return a list  (DC)
        #3400284 - Compatability fix for integer?

    Other changes:
        - Added flags to makefile for MinGW/MSYS (TC)
        - Moved variable declarations to avoid warnings with some compilers
        - Don't print space after initial #( when printing vectors.
        - Minor optimization for is_nonneg().
        - No need to round integers in OP_ROUND (#3400284)
        - Fixes to code that reports line number with error  (RC)

    Contributors:
        Kevin Cozens, Gordon McNutt, Doug Currie, Sean Long, Tim Cas, Joey,
        Richard Copley, and CMarinier.

Version 1.40
    Bugs fixed:
        #1964950 - Stop core dumps due to bad syntax in LET (and variants)
        #2826594 - allow reverse to work on empty list (Tony Garnock-Jones)
        Potential problem of arglist to foreign calls being wrongly GC'ed.
        Fixed bug that read could loop forever (tehom).

    API changes:
        Exposed is_list and list_length.
        Added scheme_register_foreign_func_list and declarations for it (tehom)
        Defined *compile-hook* (tehom)

    Other changes:
        Updated is_list and list_length to handle circular lists.
        Nested calling thru C has been made now safer (tehom)
        Peter Michaux cleaned up port_rep_from_file
        Added unwind-protect (tehom)
        Some cleanups to in/outport and Eval_Cycle by Peter Michaux
        Report error line number (Mostly by Sanel Zukan, back-compatibility by Tehom)

    Contributors:
        Kevin Cozens, Dimitrios Souflis, Tom Breton, Peter Michaux, Sanel Zukan,
        and Tony Garnock-Jones.

Version 1.39
    Bugs fixed:
        Fix for the load bug
        Fixed parsing of octal coded characters. Fixes bug #1818018.
        Added tests for when mk_vector is out of memory. Can't rely on sc->sink.
        Fix for bug #1794369
        Finished feature-request 1599947: scheme_apply0 etc return values.
        Partly provided feature-request 1599947: Expose list_length, eqv, etc
        Provided feature-request 1599945, Scheme->C->Scheme calling.
        Fix for bug 1593861 (behavior of is_integer)
        Fix for bug 1589711
        Error checking of binding spec syntax in LET and LETREC. The bad syntax
        was causing a segmentation fault in Linux. Complete fixes for bug #1817986.
        Error checking of binding spec syntax in LET*
        Bad syntax was causing core dump in Linux.
        Fix for nasty gc bug

    R5RS changes:
        R5RS requires numbers to be of equal value AND of the same type (ie. both
        exact or inexact) in order to return #t from eqv?. R5RS compliance fix.
        String output ports now conform to SRFI-6

    Other changes:
        Drew Yao fixed buffer overflow problems in mk_sharp_const.
        put OP_T0LVL in charge of reacting to EOF
        file_push checks array bounds (patch from Ray Lehtiniemi)
        Changed to always use snprintf (Patch due to Ramiro bsd1628)
        Updated usage information using text from the Manual.txt file.

Version 1.38
    Interim release until the rewrite, mostly incorporating modifications
    from Kevin Cozens. Small addition for Cygwin in the makefile, and
    modifications by Andrew Guenther for Apple platforms.

Version 1.37
    Joe Buehler submitted reserve_cells.

Version 1.36
    Joe Buehler fixed a patch in the allocator.
    Alexander Shendi moved the comment handling in the scanner, which
    fixed an obscure bug for which Mike E had provided a patch as well.
    Kevin Cozens has submitted some fixes and modifications which have
    not been incorporated yet in their entirety.

Version 1.35
    Todd Showalter discovered that the number of free cells reported
    after GC was incorrect, which could also cause unnecessary allocations.

Version 1.34
    Long missing version. Lots of bugfixes have accumulated in my email, so
    I had to start using them. In this version, Keenan Pepper has submitted
    a bugfix for the string comparison library procedure, Wouter Boeke
    modified some code that was casting to the wrong type and crashed on
    some machines, "SheppardCo" submitted a replacement "modulo" code and
    Scott Fenton submitted lots of corrections that shut up some compiler
    warnings. Brian Maher submitted instructions on how to build on OS-X.
    I have to dig deeper into my mailbox and find earlier emails, too.

Version 1.33
    Charles Hayden fixed a nasty GC bug of the new stack frame, while in
    the process of porting TinyScheme to C++. He also submitted other
    changes, and other people also had comments or requests, but the GC
    bug was so important that this version is put through the door to
    correct it.

Version 1.32
    Stephen Gildea put some quality time on TinyScheme again, and made
    a whole lot of changes to the interpreter that made it noticeably
    faster.

Version 1.31
    Patches to the hastily-done version 1.30. Stephen Gildea fixed
    some things done wrongly, and Richard Russo fixed the makefile
    for building on Windows. Property lists (heritage from MiniScheme)
    are now optional and have dissappeared from the interface. They
    should be considered as deprecated.

Version 1.30
    After many months, I followed Preston Bannister's advice of
    using macros and a single source text to keep the enums and the
    dispatch table in sync, and I used his contributed "opdefines.h".
    Timothy Downs contributed a helpful function, "scheme_call".
    Stephen Gildea contributed new versions of the makefile and
    practically all other sources. He created a built-in STRING-APPEND,
    and fixed a lot of other bugs.
    Ruhi Bloodworth reported fixes necessary for OS X and a small
    bug in dynload.c.

Version 1.29
    The previous version contained a lot of corrections, but there
    were a lot more that still wait on a sheet of paper lost in a
    carton someplace after my house move... Manuel Heras-Gilsanz
    noticed this and resent his own contribution, which relies on
    another bugfix that v.1.28 was missing: a problem with string
    output, that this version fixes. I hope other people will take
    the time to resend their contributions, if they didn't make it
    to v.1.28.

Version 1.28
    Many people have contacted me with bugfixes or remarks in
    the three months I was inactive. A lot of them spotted that
    scheme_deinit crashed while reporting gc results. They suggested
    that sc->outport be set to NIL in scheme_deinit, which I did.
    Dennis Taylor remarked that OP_VALUEPRINT reset sc->value instead
    of preserving it. He submitted a modification which I adopted
    partially. David Hovemeyer sent me many little changes, that you
    will find in version 1.28, and Partice Stoessel modified the
    float reader to conform to R5RS.

Version 1.27
    Version 1.27 is the successor of 1.25. Bug fixes only, but I had to
    release them so that everybody can profit. 'Backchar' tried to write
    back to the string, which obviously didn't work for const strings.
    'Substring' didn't check for crossed start and end indices. Defines
    changed to restore the ability to compile under MSVC.

Version 1.26
    Version 1.26 was never released. I changed a lot of things, in fact
    too much, even the garbage collector, and hell broke loose. I'll
    try a more gradual approach next time.

Version 1.25
    Types have been homogenized to be able to accommodate a different
    representation. Plus, promises are no longer closures. Unfortunately,
    I discovered that continuations and force/delay do not pass the SCM
    test (and never did)... However, on the bright side, what little
    modifications I did had a large impact on the footprint:
    USE_NO_FEATURES now produces an object file of 63960 bytes on Linux!

Version 1.24
    SCM tests now pass again after change in atom2str.

Version 1.23
    Finally I managed to mess it up with my version control. Version
    1.22 actually lacked some of the things I have been fixing in the
    meantime. This should be considered as a complete replacement for
    1.22.

Version 1.22
    The new ports had a bug in LOAD. MK_CLOSURE is introduced.
    Shawn Wagner inquired about string->number and number->string.
    I added string->atom and atom->string and defined the number
    functions from them. Doing that, I fixed WRITE applied to symbols
    (it didn't quote them). Unfortunately, minimum build is now
    slightly larger than 64k... I postpone action because Jason's idea
    might solve it elegantly.

Version 1.21
    Jason Felice submitted a radically different datatype representation
    which he had implemented. While discussing its pros and cons, it
    became apparent that the current implementation of ports suffered
    from a grave fault: ports were not garbage-collected. I changed the
    ports to be heap-allocated, which enabled the use of string ports
    for loading. Jason also fixed errors in the garbage collection of
    vectors. USE_VERBATIM is gone. "ssp_compiler.c" has a better solution
    on HTML generation. A bug involving backslash notation in strings
    has been fixed. '-c' flag now executes next argument as a stream of
    Scheme commands. Foreign functions are now also heap allocated,
    and scheme_define is used to define everything.

Version 1.20
    Tracing has been added. The toplevel loop has been slightly
    rearranged. Backquote reading for vector templates has been
    sanitized. Symbol interning is now correct. Arithmetic functions
    have been corrected. APPLY, MAP, FOR-EACH, numeric comparison
    functions fixed. String reader/writer understands \xAA notation.

Version 1.19
    Carriage Return now delimits identifiers. DOS-formatted Scheme files
    can be used by Unix. Random number generator added to library.
    Fixed some glitches of the new type-checking scheme. Fixed erroneous
    (append '() 'a) behavior. Will continue with r4rstest.scm to
    fix errors.

Version 1.18
    The FFI has been extended. USE_VERBOSE_GC has gone. Anyone wanting
    the same functionality can put (gcverbose #t) in init.scm.
    print-width was removed, along with three corresponding op-codes.
    Extended character constants with ASCII names were added.
    mk_counted_string paves the way for full support of binary strings.
    As much as possible of the type-checking chores were delegated
    to the inner loop, thus reducing the code size to less than 4200 loc!

Version 1.17
    Dynamically-loaded extensions are more fully integrated.
    TinyScheme is now distributed under the BSD open-source license.

Version 1.16
    Dynamically-loaded extensions introduced (USE_DL).
    Santeri Paavolainen found a race condition: When a cons is executed,
    and each of the two arguments is a constructing function,  GC could
    happen before all arguments are evaluated and cons() is called, and
    the evaluated arguments would all be reclaimed!
    Fortunately, such a case was rare in the code, although it is
    a pitfall in new code and code in foreign functions. Currently, only
    one such case remains, when COLON_HOOK is defined.

Version 1.15
    David Gould also contributed some changes that speed up operation.
    Kirk Zurell fixed HASPROP.
    The Garbage Collection didn't collect all the garbage...fixed.

Version 1.14
    Unfortunately, after Andre fixed the GC it became obvious that the
    algorithm was too slow... Fortunately, David Gould found a way to
    speed it up.

Version 1.13
    Silly bug involving division by zero resolved by Roland Kaufman.
    Macintoch support from Shmulik Regev.
    Float parser bug fixed by Alexander Shendi.
    GC bug from Andru Luvisi.

Version 1.12
    Cis* incorrectly called isalpha() instead of isascii()
    Added USE_CHAR_CLASSIFIERS, USE_STRING_PORTS.

Version 1.11
    BSDI defines isnumber... changed all similar functions to is_*
    EXPT now has correct definition. Added FLOOR,CEILING,TRUNCATE
    and ROUND, courtesy of Bengt Kleberg. Preprocessor symbols now
    have values 1 or 0, and can be set as compiler defines (proposed
    by Andy Ganor *months* ago). 'prompt' and 'InitFile' can now be
    defined during compilation, too.

Version 1.10
    Another bug when file ends with comment!
    Added DEFINE-MACRO in init.scm, courtesy of Andy Gaynor.

Version 1.09
    Removed bug when READ met EOF. lcm.

Version 1.08
    quotient,remainder and modulo. gcd.

Version 1.07
    '=>' in cond now exists
    list? now checks for circularity
    some reader bugs removed
    Reader is more consistent wrt vectors
    Quote and Quasiquote work with vectors

Version 1.06
    #! is now skipped
    generic-assoc bug removed
    strings are now managed differently, hack.txt is removed
    various delicate points fixed

Version 1.05
    Support for scripts, *args*, "-1" option.
    Various R5RS procedures.
    *sharp-hook*
    Handles unmatched parentheses.
    New architecture for procedures.

Version 1.04
    Added missing T_ATOM bits...
    Added vectors
    Free-list is sorted by address, since vectors need consecutive cells.
    (quit <exitcode>) for use with scripts

Version 1.03 (26 Aug 1998):
    Extended .h with useful functions for FFI
    Library: with-input-* etc.
    Finished R5RS I/O, added string ports.

Version 1.02 (25 Aug 1998):
    First part of R5RS I/O.

-
+ 8318EB755F17767FAC29DFC265973F0355BC973BFA42895E9D353126A9CA4969CE53332D255F5DF8B0C3E3715B5F2C168A5BC30BE5C8DB8C39B27D4D1FA48173
bitcoin/src/shiva/COPYING

(0 . 0)(1 . 31)
                         LICENSE TERMS

Copyright (c) 2000, Dimitrios Souflis
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.

Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.

Neither the name of Dimitrios Souflis nor the names of the
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR 
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

-
+ 37B242324EBF0BAB3BC67812F23111C84D70420348F47F1CB617856E9F18A5E11A30D2CD0CEBB802BC435588BFC49AF3A50D8EB24674A795B83102809C52D3AE
bitcoin/src/shiva/hack.txt

(0 . 0)(1 . 244)

                              How to hack TinyScheme
                              ----------------------

     TinyScheme is easy to learn and modify. It is structured like a
     meta-interpreter, only it is written in C. All data are Scheme
     objects, which facilitates both understanding/modifying the
     code and reifying the interpreter workings.

     In place of a dry description, we will pace through the addition
     of a useful new datatype: garbage-collected memory blocks.
     The interface will be:

          (make-block <n> [<fill>]) makes a new block of the specified size
               optionally filling it with a specified byte
          (block? <obj>)
          (block-length <block>)
          (block-ref <block> <index>) retrieves byte at location
          (block-set! <block> <index> <byte>) modifies byte at location
     
     In the sequel, lines that begin with '>' denote lines to add to the
     code. Lines that begin with '|' are just citations of existing code.
     Lines that begin with X denote lines to be removed from the code.

     First of all, we need to assign a typeid to our new type. Typeids
     in TinyScheme are small integers declared in the scheme_types enum
     located near the top of the scheme.c file; it begins with T_STRING.
     Add a new entry at the end, say T_MEMBLOCK. Remember to adjust the
     value of T_LAST_SYTEM_TYPE when adding new entries. There can be at
     most 31 types, but you don't have to worry about that limit yet.

|       T_ENVIRONMENT=14,
X       T_LAST_SYSTEM_TYPE=14
>       T_MEMBLOCK=15,
>       T_LAST_SYSTEM_TYPE=15
|     };


     Then, some helper macros would be useful. Go to where is_string()
     and the rest are defined and add:

>     INTERFACE INLINE int is_memblock(pointer p)     { return (type(p)==T_MEMBLOCK); }

     This actually is a function, because it is meant to be exported by
     scheme.h. If no foreign function will ever manipulate a memory block,
     you can instead define it as a macro:

>     #define is_memblock(p) (type(p)==T_MEMBLOCK)

     Then we make space for the new type in the main data structure:
     struct cell. As it happens, the _string part of the union _object
     (that is used to hold character strings) has two fields that suit us:

|         struct {
|              char   *_svalue;
|              int   _keynum;
|         } _string;

     We can use _svalue to hold the actual pointer and _keynum to hold its
     length. If we couln't reuse existing fields, we could always add other
     alternatives in union _object.

     We then proceed to write the function that actually makes a new block.
     For conformance reasons, we name it mk_memblock

>     static pointer mk_memblock(scheme *sc, int len, char fill) {
>          pointer x;
>          char *p=(char*)sc->malloc(len);
>
>          if(p==0) {
>               return sc->NIL;
>          }
>          x = get_cell(sc, sc->NIL, sc->NIL);
>
>          typeflag(x) = T_MEMBLOCK|T_ATOM;
>          strvalue(x)=p;
>          keynum(x)=len;
>          memset(p,fill,len);
>          return (x);
>     }

     The memory used by the MEMBLOCK will have to be freed when the cell
     is reclaimed during garbage collection. There is a placeholder for
     that staff, function finalize_cell(), currently handling strings only.

|     static void finalize_cell(scheme *sc, pointer a) {
|       if(is_string(a)) {
|          sc->free(strvalue(a));
>       } else if(is_memblock(a)) {
>          sc->free(strvalue(a));
|       } else if(is_port(a)) {

     There are no MEMBLOCK literals, so we don't concern ourselves with
     the READER part (yet!). We must cater to the PRINTER, though. We
     add one case more in atom2str().

|     } else if (iscontinuation(l)) {
|          p = "#<CONTINUATION>";
>     } else if (is_memblock(l)) {
>          p = "#<MEMORY BLOCK>";
|     } else {

     Whenever a MEMBLOCK is displayed, it will look like that.
     Now, we must add the interface functions: constructor, predicate,
     accessor, modifier. We must in fact create new op-codes for the virtual
     machine underlying TinyScheme. Since version 1.30, TinyScheme uses
     macros and a single source text to keep the enums and the dispatch table
     in sync. The op-codes are defined in the opdefines.h file with one line
     for each op-code. The lines in the file have six columns between the
     starting _OPDEF( and ending ): A, B, C, D, E, and OP.
     Note that this file uses unusually long lines to accomodate all the
     information; adjust your editor to handle this.

     The purpose of the columns is:
       - Column A is the name of the subroutine that handles the op-code.
       - Column B is the name of the op-code function.
       - Columns C and D are the minimum and maximum number of arguments
         that are accepted by the op-code.
       - Column E is a set of flags that tells the interpreter the type of
         each of the arguments expected by the op-code.
       - Column OP is used in the scheme_opcodes enum located in the
         scheme-private.h file.

     Op-codes are really just tags for a huge C switch, only this switch
     is broken up in to a number of different opexe_X functions. The
     correspondence is made in table "dispatch_table". There, we assign
     the new op-codes to opexe_2, where the equivalent ones for vectors
     are situated. We also assign a name for them, and specify the minimum
     and maximum arity (number of expected arguments). INF_ARG as a maximum
     arity means "unlimited".

     For reasons of consistency, we add the new op-codes right after those
     for vectors:

|     _OP_DEF(opexe_2, "vector-set!",                    3,  3,       TST_VECTOR TST_NATURAL TST_ANY,  OP_VECSET           )
>     _OP_DEF(opexe_2, "make-block",                     1,  2,       TST_NATURAL TST_CHAR,            OP_MKBLOCK          )
>     _OP_DEF(opexe_2, "block-length",                   1,  1,       T_MEMBLOCK,                      OP_BLOCKLEN         )
>     _OP_DEF(opexe_2, "block-ref",                      2,  2,       T_MEMBLOCK TST_NATURAL,          OP_BLOCKREF         )
>     _OP_DEF(opexe_2, "block-set!",                     1,  1,       T_MEMBLOCK TST_NATURAL TST_CHAR, OP_BLOCKSET         )
|     _OP_DEF(opexe_3, "not",                            1,  1,       TST_NONE,                        OP_NOT              )

     We add the predicate along with the other predicates in opexe_3:

|     _OP_DEF(opexe_3, "vector?",                        1,  1,       TST_ANY,                         OP_VECTORP          )
>     _OP_DEF(opexe_3, "block?",                         1,  1,       TST_ANY,                         OP_BLOCKP           )
|     _OP_DEF(opexe_3, "eq?",                            2,  2,       TST_ANY,                         OP_EQ               )

     All that remains is to write the actual code to do the processing and
     add it to the switch statement in opexe_2, after the OP_VECSET case.

>     case OP_MKBLOCK: { /* make-block */
>          int fill=0;
>          int len;
>
>          if(!isnumber(car(sc->args))) {
>               Error_1(sc,"make-block: not a number:",car(sc->args));
>          }
>          len=ivalue(car(sc->args));
>          if(len<=0) {
>               Error_1(sc,"make-block: not positive:",car(sc->args));
>          }
>
>          if(cdr(sc->args)!=sc->NIL) {
>               if(!isnumber(cadr(sc->args)) || ivalue(cadr(sc->args))<0) {
>                    Error_1(sc,"make-block: not a positive number:",cadr(sc->args));
>               }
>               fill=charvalue(cadr(sc->args))%255;
>          }
>          s_return(sc,mk_memblock(sc,len,(char)fill));
>     }
>
>     case OP_BLOCKLEN:  /* block-length */
>          if(!ismemblock(car(sc->args))) {
>               Error_1(sc,"block-length: not a memory block:",car(sc->args));
>          }
>          s_return(sc,mk_integer(sc,keynum(car(sc->args))));
>
>     case OP_BLOCKREF: { /* block-ref */
>          char *str;
>          int index;
>
>          if(!ismemblock(car(sc->args))) {
>               Error_1(sc,"block-ref: not a memory block:",car(sc->args));
>          }
>          str=strvalue(car(sc->args));
>
>          if(cdr(sc->args)==sc->NIL) {
>               Error_0(sc,"block-ref: needs two arguments");
>          }
>          if(!isnumber(cadr(sc->args))) {
>               Error_1(sc,"block-ref: not a number:",cadr(sc->args));
>          }
>          index=ivalue(cadr(sc->args));
>
>          if(index<0 || index>=keynum(car(sc->args))) {
>               Error_1(sc,"block-ref: out of bounds:",cadr(sc->args));
>          }
>
>          s_return(sc,mk_integer(sc,str[index]));
>     }
>
>     case OP_BLOCKSET: { /* block-set! */
>          char *str;
>          int index;
>          int c;
>
>          if(!ismemblock(car(sc->args))) {
>               Error_1(sc,"block-set!: not a memory block:",car(sc->args));
>          }
>          if(isimmutable(car(sc->args))) {
>               Error_1(sc,"block-set!: unable to alter immutable memory block:",car(sc->args));
>          }
>          str=strvalue(car(sc->args));
>
>          if(cdr(sc->args)==sc->NIL) {
>               Error_0(sc,"block-set!: needs three arguments");
>          }
>          if(!isnumber(cadr(sc->args))) {
>               Error_1(sc,"block-set!: not a number:",cadr(sc->args));
>          }
>          index=ivalue(cadr(sc->args));
>          if(index<0 || index>=keynum(car(sc->args))) {
>               Error_1(sc,"block-set!: out of bounds:",cadr(sc->args));
>          }
>
>          if(cddr(sc->args)==sc->NIL) {
>               Error_0(sc,"block-set!: needs three arguments");
>          }
>          if(!isinteger(caddr(sc->args))) {
>               Error_1(sc,"block-set!: not an integer:",caddr(sc->args));
>          }
>          c=ivalue(caddr(sc->args))%255;
>
>          str[index]=(char)c;
>          s_return(sc,car(sc->args));
>     }

     Finally, do the same for the predicate in opexe_3.

|     case OP_VECTORP:     /* vector? */
|          s_retbool(is_vector(car(sc->args)));
>     case OP_BLOCKP:     /* block? */
>          s_retbool(is_memblock(car(sc->args)));
|     case OP_EQ:         /* eq? */

-
+ 816C72CA3FE3ED9F9A2C1C1E779ADCA1279EDABAF547E70D5BBEBD00300C2062D7C2BA51A3ED200472639640577FB3643D780E204546ACA62807978BA3F54449
bitcoin/src/shiva/init.scm

(0 . 0)(1 . 716)
;    Initialization file for TinySCHEME 1.41

; Per R5RS, up to four deep compositions should be defined
(define (caar x) (car (car x)))
(define (cadr x) (car (cdr x)))
(define (cdar x) (cdr (car x)))
(define (cddr x) (cdr (cdr x)))
(define (caaar x) (car (car (car x))))
(define (caadr x) (car (car (cdr x))))
(define (cadar x) (car (cdr (car x))))
(define (caddr x) (car (cdr (cdr x))))
(define (cdaar x) (cdr (car (car x))))
(define (cdadr x) (cdr (car (cdr x))))
(define (cddar x) (cdr (cdr (car x))))
(define (cdddr x) (cdr (cdr (cdr x))))
(define (caaaar x) (car (car (car (car x)))))
(define (caaadr x) (car (car (car (cdr x)))))
(define (caadar x) (car (car (cdr (car x)))))
(define (caaddr x) (car (car (cdr (cdr x)))))
(define (cadaar x) (car (cdr (car (car x)))))
(define (cadadr x) (car (cdr (car (cdr x)))))
(define (caddar x) (car (cdr (cdr (car x)))))
(define (cadddr x) (car (cdr (cdr (cdr x)))))
(define (cdaaar x) (cdr (car (car (car x)))))
(define (cdaadr x) (cdr (car (car (cdr x)))))
(define (cdadar x) (cdr (car (cdr (car x)))))
(define (cdaddr x) (cdr (car (cdr (cdr x)))))
(define (cddaar x) (cdr (cdr (car (car x)))))
(define (cddadr x) (cdr (cdr (car (cdr x)))))
(define (cdddar x) (cdr (cdr (cdr (car x)))))
(define (cddddr x) (cdr (cdr (cdr (cdr x)))))

;;;; Utility to ease macro creation
(define (macro-expand form)
     ((eval (get-closure-code (eval (car form)))) form))

(define (macro-expand-all form)
   (if (macro? form)
      (macro-expand-all (macro-expand form))
      form))

(define *compile-hook* macro-expand-all)


(macro (unless form)
     `(if (not ,(cadr form)) (begin ,@(cddr form))))

(macro (when form)
     `(if ,(cadr form) (begin ,@(cddr form))))

; DEFINE-MACRO Contributed by Andy Gaynor
(macro (define-macro dform)
  (if (symbol? (cadr dform))
    `(macro ,@(cdr dform))
    (let ((form (gensym)))
      `(macro (,(caadr dform) ,form)
         (apply (lambda ,(cdadr dform) ,@(cddr dform)) (cdr ,form))))))

; Utilities for math. Notice that inexact->exact is primitive,
; but exact->inexact is not.
(define exact? integer?)
(define (inexact? x) (and (real? x) (not (integer? x))))
(define (even? n) (= (remainder n 2) 0))
(define (odd? n) (not (= (remainder n 2) 0)))
(define (zero? n) (= n 0))
(define (positive? n) (> n 0))
(define (negative? n) (< n 0))
(define complex? number?)
(define rational? real?)
(define (abs n) (if (>= n 0) n (- n)))
(define (exact->inexact n) (* n 1.0))
(define (<> n1 n2) (not (= n1 n2)))

; min and max must return inexact if any arg is inexact; use (+ n 0.0)
(define (max . lst)
  (foldr (lambda (a b)
           (if (> a b)
             (if (exact? b) a (+ a 0.0))
             (if (exact? a) b (+ b 0.0))))
         (car lst) (cdr lst)))
(define (min . lst)
  (foldr (lambda (a b)
           (if (< a b)
             (if (exact? b) a (+ a 0.0))
             (if (exact? a) b (+ b 0.0))))
         (car lst) (cdr lst)))

(define (succ x) (+ x 1))
(define (pred x) (- x 1))
(define gcd
  (lambda a
    (if (null? a)
      0
      (let ((aa (abs (car a)))
            (bb (abs (cadr a))))
         (if (= bb 0)
              aa
              (gcd bb (remainder aa bb)))))))
(define lcm
  (lambda a
    (if (null? a)
      1
      (let ((aa (abs (car a)))
            (bb (abs (cadr a))))
         (if (or (= aa 0) (= bb 0))
             0
             (abs (* (quotient aa (gcd aa bb)) bb)))))))


(define (string . charlist)
     (list->string charlist))

(define (list->string charlist)
     (let* ((len (length charlist))
            (newstr (make-string len))
            (fill-string!
               (lambda (str i len charlist)
                    (if (= i len)
                         str
                         (begin (string-set! str i (car charlist))
                         (fill-string! str (+ i 1) len (cdr charlist)))))))
          (fill-string! newstr 0 len charlist)))

(define (string-fill! s e)
     (let ((n (string-length s)))
          (let loop ((i 0))
               (if (= i n)
                    s
                    (begin (string-set! s i e) (loop (succ i)))))))

(define (string->list s)
     (let loop ((n (pred (string-length s))) (l '()))
          (if (= n -1)
               l
               (loop (pred n) (cons (string-ref s n) l)))))

(define (string-copy str)
     (string-append str))

(define (string->anyatom str pred)
     (let* ((a (string->atom str)))
       (if (pred a) a
         (error "string->xxx: not a xxx" a))))

(define (string->number str . base)
    (let ((n (string->atom str (if (null? base) 10 (car base)))))
        (if (number? n) n #f)))

(define (anyatom->string n pred)
  (if (pred n)
      (atom->string n)
      (error "xxx->string: not a xxx" n)))

(define (number->string n . base)
    (atom->string n (if (null? base) 10 (car base))))


(define (char-cmp? cmp a b)
     (cmp (char->integer a) (char->integer b)))
(define (char-ci-cmp? cmp a b)
     (cmp (char->integer (char-downcase a)) (char->integer (char-downcase b))))

(define (char=? a b) (char-cmp? = a b))
(define (char<? a b) (char-cmp? < a b))
(define (char>? a b) (char-cmp? > a b))
(define (char<=? a b) (char-cmp? <= a b))
(define (char>=? a b) (char-cmp? >= a b))

(define (char-ci=? a b) (char-ci-cmp? = a b))
(define (char-ci<? a b) (char-ci-cmp? < a b))
(define (char-ci>? a b) (char-ci-cmp? > a b))
(define (char-ci<=? a b) (char-ci-cmp? <= a b))
(define (char-ci>=? a b) (char-ci-cmp? >= a b))

; Note the trick of returning (cmp x y)
(define (string-cmp? chcmp cmp a b)
     (let ((na (string-length a)) (nb (string-length b)))
          (let loop ((i 0))
               (cond
                    ((= i na)
                         (if (= i nb) (cmp 0 0) (cmp 0 1)))
                    ((= i nb)
                         (cmp 1 0))
                    ((chcmp = (string-ref a i) (string-ref b i))
                         (loop (succ i)))
                    (else
                         (chcmp cmp (string-ref a i) (string-ref b i)))))))


(define (string=? a b) (string-cmp? char-cmp? = a b))
(define (string<? a b) (string-cmp? char-cmp? < a b))
(define (string>? a b) (string-cmp? char-cmp? > a b))
(define (string<=? a b) (string-cmp? char-cmp? <= a b))
(define (string>=? a b) (string-cmp? char-cmp? >= a b))

(define (string-ci=? a b) (string-cmp? char-ci-cmp? = a b))
(define (string-ci<? a b) (string-cmp? char-ci-cmp? < a b))
(define (string-ci>? a b) (string-cmp? char-ci-cmp? > a b))
(define (string-ci<=? a b) (string-cmp? char-ci-cmp? <= a b))
(define (string-ci>=? a b) (string-cmp? char-ci-cmp? >= a b))

(define (list . x) x)

(define (foldr f x lst)
     (if (null? lst)
          x
          (foldr f (f x (car lst)) (cdr lst))))

(define (unzip1-with-cdr . lists)
  (unzip1-with-cdr-iterative lists '() '()))

(define (unzip1-with-cdr-iterative lists cars cdrs)
  (if (null? lists)
      (cons cars cdrs)
      (let ((car1 (caar lists))
            (cdr1 (cdar lists)))
        (unzip1-with-cdr-iterative
          (cdr lists)
          (append cars (list car1))
          (append cdrs (list cdr1))))))

(define (map proc . lists)
  (if (null? lists)
      (apply proc)
      (if (null? (car lists))
        '()
        (let* ((unz (apply unzip1-with-cdr lists))
               (cars (car unz))
               (cdrs (cdr unz)))
          (cons (apply proc cars) (apply map (cons proc cdrs)))))))

(define (for-each proc . lists)
  (if (null? lists)
      (apply proc)
      (if (null? (car lists))
        #t
        (let* ((unz (apply unzip1-with-cdr lists))
               (cars (car unz))
               (cdrs (cdr unz)))
          (apply proc cars) (apply map (cons proc cdrs))))))

(define (list-tail x k)
    (if (zero? k)
        x
        (list-tail (cdr x) (- k 1))))

(define (list-ref x k)
    (car (list-tail x k)))

(define (last-pair x)
    (if (pair? (cdr x))
        (last-pair (cdr x))
        x))

(define (head stream) (car stream))

(define (tail stream) (force (cdr stream)))

(define (vector-equal? x y)
     (and (vector? x) (vector? y) (= (vector-length x) (vector-length y))
          (let ((n (vector-length x)))
               (let loop ((i 0))
                    (if (= i n)
                         #t
                         (and (equal? (vector-ref x i) (vector-ref y i))
                              (loop (succ i))))))))

(define (list->vector x)
     (apply vector x))

(define (vector-fill! v e)
     (let ((n (vector-length v)))
          (let loop ((i 0))
               (if (= i n)
                    v
                    (begin (vector-set! v i e) (loop (succ i)))))))

(define (vector->list v)
     (let loop ((n (pred (vector-length v))) (l '()))
          (if (= n -1)
               l
               (loop (pred n) (cons (vector-ref v n) l)))))

;; The following quasiquote macro is due to Eric S. Tiedemann.
;;   Copyright 1988 by Eric S. Tiedemann; all rights reserved.
;;
;; Subsequently modified to handle vectors: D. Souflis

(macro
 quasiquote
 (lambda (l)
   (define (mcons f l r)
     (if (and (pair? r)
              (eq? (car r) 'quote)
              (eq? (car (cdr r)) (cdr f))
              (pair? l)
              (eq? (car l) 'quote)
              (eq? (car (cdr l)) (car f)))
         (if (or (procedure? f) (number? f) (string? f))
               f
               (list 'quote f))
         (if (eqv? l vector)
               (apply l (eval r))
               (list 'cons l r)
               )))
   (define (mappend f l r)
     (if (or (null? (cdr f))
             (and (pair? r)
                  (eq? (car r) 'quote)
                  (eq? (car (cdr r)) '())))
         l
         (list 'append l r)))
   (define (foo level form)
     (cond ((not (pair? form))
               (if (or (procedure? form) (number? form) (string? form))
                    form
                    (list 'quote form))
               )
           ((eq? 'quasiquote (car form))
            (mcons form ''quasiquote (foo (+ level 1) (cdr form))))
           (#t (if (zero? level)
                   (cond ((eq? (car form) 'unquote) (car (cdr form)))
                         ((eq? (car form) 'unquote-splicing)
                          (error "Unquote-splicing wasn't in a list:"
                                 form))
                         ((and (pair? (car form))
                               (eq? (car (car form)) 'unquote-splicing))
                          (mappend form (car (cdr (car form)))
                                   (foo level (cdr form))))
                         (#t (mcons form (foo level (car form))
                                         (foo level (cdr form)))))
                   (cond ((eq? (car form) 'unquote)
                          (mcons form ''unquote (foo (- level 1)
                                                     (cdr form))))
                         ((eq? (car form) 'unquote-splicing)
                          (mcons form ''unquote-splicing
                                      (foo (- level 1) (cdr form))))
                         (#t (mcons form (foo level (car form))
                                         (foo level (cdr form)))))))))
   (foo 0 (car (cdr l)))))

;;;;;Helper for the dynamic-wind definition.  By Tom Breton (Tehom)
(define (shared-tail x y)
   (let ((len-x (length x))
         (len-y (length y)))
      (define (shared-tail-helper x y)
         (if
            (eq? x y)
            x
            (shared-tail-helper (cdr x) (cdr y))))

      (cond
         ((> len-x len-y)
            (shared-tail-helper
               (list-tail x (- len-x len-y))
               y))
         ((< len-x len-y)
            (shared-tail-helper
               x
               (list-tail y (- len-y len-x))))
         (#t (shared-tail-helper x y)))))

;;;;;Dynamic-wind by Tom Breton (Tehom)

;;Guarded because we must only eval this once, because doing so
;;redefines call/cc in terms of old call/cc
(unless (defined? 'dynamic-wind)
   (let
      ;;These functions are defined in the context of a private list of
      ;;pairs of before/after procs.
      (  (*active-windings* '())
         ;;We'll define some functions into the larger environment, so
         ;;we need to know it.
         (outer-env (current-environment)))

      ;;Poor-man's structure operations
      (define before-func car)
      (define after-func  cdr)
      (define make-winding cons)

      ;;Manage active windings
      (define (activate-winding! new)
         ((before-func new))
         (set! *active-windings* (cons new *active-windings*)))
      (define (deactivate-top-winding!)
         (let ((old-top (car *active-windings*)))
            ;;Remove it from the list first so it's not active during its
            ;;own exit.
            (set! *active-windings* (cdr *active-windings*))
            ((after-func old-top))))

      (define (set-active-windings! new-ws)
         (unless (eq? new-ws *active-windings*)
            (let ((shared (shared-tail new-ws *active-windings*)))

               ;;Define the looping functions.
               ;;Exit the old list.  Do deeper ones last.  Don't do
               ;;any shared ones.
               (define (pop-many)
                  (unless (eq? *active-windings* shared)
                     (deactivate-top-winding!)
                     (pop-many)))
               ;;Enter the new list.  Do deeper ones first so that the
               ;;deeper windings will already be active.  Don't do any
               ;;shared ones.
               (define (push-many new-ws)
                  (unless (eq? new-ws shared)
                     (push-many (cdr new-ws))
                     (activate-winding! (car new-ws))))

               ;;Do it.
               (pop-many)
               (push-many new-ws))))

      ;;The definitions themselves.
      (eval
         `(define call-with-current-continuation
             ;;It internally uses the built-in call/cc, so capture it.
             ,(let ((old-c/cc call-with-current-continuation))
                 (lambda (func)
                    ;;Use old call/cc to get the continuation.
                    (old-c/cc
                       (lambda (continuation)
                          ;;Call func with not the continuation itself
                          ;;but a procedure that adjusts the active
                          ;;windings to what they were when we made
                          ;;this, and only then calls the
                          ;;continuation.
                          (func
                             (let ((current-ws *active-windings*))
                                (lambda (x)
                                   (set-active-windings! current-ws)
                                   (continuation x)))))))))
         outer-env)
      ;;We can't just say "define (dynamic-wind before thunk after)"
      ;;because the lambda it's defined to lives in this environment,
      ;;not in the global environment.
      (eval
         `(define dynamic-wind
             ,(lambda (before thunk after)
                 ;;Make a new winding
                 (activate-winding! (make-winding before after))
                 (let ((result (thunk)))
                    ;;Get rid of the new winding.
                    (deactivate-top-winding!)
                    ;;The return value is that of thunk.
                    result)))
         outer-env)))

(define call/cc call-with-current-continuation)


;;;;; atom? and equal? written by a.k

;;;; atom?
(define (atom? x)
  (not (pair? x)))

;;;;    equal?
(define (equal? x y)
     (cond
          ((pair? x)
               (and (pair? y)
                    (equal? (car x) (car y))
                    (equal? (cdr x) (cdr y))))
          ((vector? x)
               (and (vector? y) (vector-equal? x y)))
          ((string? x)
               (and (string? y) (string=? x y)))
          (else (eqv? x y))))

;;;; (do ((var init inc) ...) (endtest result ...) body ...)
;;
(macro do
  (lambda (do-macro)
    (apply (lambda (do vars endtest . body)
             (let ((do-loop (gensym)))
               `(letrec ((,do-loop
                           (lambda ,(map (lambda (x)
                                           (if (pair? x) (car x) x))
                                      `,vars)
                             (if ,(car endtest)
                               (begin ,@(cdr endtest))
                               (begin
                                 ,@body
                                 (,do-loop
                                   ,@(map (lambda (x)
                                            (cond
                                              ((not (pair? x)) x)
                                              ((< (length x) 3) (car x))
                                              (else (car (cdr (cdr x))))))
                                       `,vars)))))))
                  (,do-loop
                    ,@(map (lambda (x)
                             (if (and (pair? x) (cdr x))
                               (car (cdr x))
                               '()))
                        `,vars)))))
      do-macro)))

;;;; generic-member
(define (generic-member cmp obj lst)
  (cond
    ((null? lst) #f)
    ((cmp obj (car lst)) lst)
    (else (generic-member cmp obj (cdr lst)))))

(define (memq obj lst)
     (generic-member eq? obj lst))
(define (memv obj lst)
     (generic-member eqv? obj lst))
(define (member obj lst)
     (generic-member equal? obj lst))

;;;; generic-assoc
(define (generic-assoc cmp obj alst)
     (cond
          ((null? alst) #f)
          ((cmp obj (caar alst)) (car alst))
          (else (generic-assoc cmp obj (cdr alst)))))

(define (assq obj alst)
     (generic-assoc eq? obj alst))
(define (assv obj alst)
     (generic-assoc eqv? obj alst))
(define (assoc obj alst)
     (generic-assoc equal? obj alst))

(define (acons x y z) (cons (cons x y) z))

;;;; Handy for imperative programs
;;;; Used as: (define-with-return (foo x y) .... (return z) ...)
(macro (define-with-return form)
     `(define ,(cadr form)
          (call/cc (lambda (return) ,@(cddr form)))))

;;;; Simple exception handling
;
;    Exceptions are caught as follows:
;
;         (catch (do-something to-recover and-return meaningful-value)
;              (if-something goes-wrong)
;              (with-these calls))
;
;    "Catch" establishes a scope spanning multiple call-frames
;    until another "catch" is encountered.
;
;    Exceptions are thrown with:
;
;         (throw "message")
;
;    If used outside a (catch ...), reverts to (error "message)

(define *handlers* (list))

(define (push-handler proc)
     (set! *handlers* (cons proc *handlers*)))

(define (pop-handler)
     (let ((h (car *handlers*)))
          (set! *handlers* (cdr *handlers*))
          h))

(define (more-handlers?)
     (pair? *handlers*))

(define (throw . x)
     (if (more-handlers?)
          (apply (pop-handler))
          (apply error x)))

(macro (catch form)
     (let ((label (gensym)))
          `(call/cc (lambda (exit)
               (push-handler (lambda () (exit ,(cadr form))))
               (let ((,label (begin ,@(cddr form))))
                    (pop-handler)
                    ,label)))))

(define *error-hook* throw)


;;;;; Definition of MAKE-ENVIRONMENT, to be used with two-argument EVAL

(macro (make-environment form)
     `(apply (lambda ()
               ,@(cdr form)
               (current-environment))))

(define-macro (eval-polymorphic x . envl)
  (display envl)
  (let* ((env (if (null? envl) (current-environment) (eval (car envl))))
         (xval (eval x env)))
    (if (closure? xval)
      (make-closure (get-closure-code xval) env)
      xval)))

; Redefine this if you install another package infrastructure
; Also redefine 'package'
(define *colon-hook* eval)

;;;;; I/O

(define (input-output-port? p)
     (and (input-port? p) (output-port? p)))

(define (close-port p)
     (cond
          ((input-output-port? p) (close-input-port (close-output-port p)))
          ((input-port? p) (close-input-port p))
          ((output-port? p) (close-output-port p))
          (else (throw "Not a port" p))))

(define (call-with-input-file s p)
     (let ((inport (open-input-file s)))
          (if (eq? inport #f)
               #f
               (let ((res (p inport)))
                    (close-input-port inport)
                    res))))

(define (call-with-output-file s p)
     (let ((outport (open-output-file s)))
          (if (eq? outport #f)
               #f
               (let ((res (p outport)))
                    (close-output-port outport)
                    res))))

(define (with-input-from-file s p)
     (let ((inport (open-input-file s)))
          (if (eq? inport #f)
               #f
               (let ((prev-inport (current-input-port)))
                    (set-input-port inport)
                    (let ((res (p)))
                         (close-input-port inport)
                         (set-input-port prev-inport)
                         res)))))

(define (with-output-to-file s p)
     (let ((outport (open-output-file s)))
          (if (eq? outport #f)
               #f
               (let ((prev-outport (current-output-port)))
                    (set-output-port outport)
                    (let ((res (p)))
                         (close-output-port outport)
                         (set-output-port prev-outport)
                         res)))))

(define (with-input-output-from-to-files si so p)
     (let ((inport (open-input-file si))
           (outport (open-input-file so)))
          (if (not (and inport outport))
               (begin
                    (close-input-port inport)
                    (close-output-port outport)
                    #f)
               (let ((prev-inport (current-input-port))
                     (prev-outport (current-output-port)))
                    (set-input-port inport)
                    (set-output-port outport)
                    (let ((res (p)))
                         (close-input-port inport)
                         (close-output-port outport)
                         (set-input-port prev-inport)
                         (set-output-port prev-outport)
                         res)))))

; Random number generator (maximum cycle)
(define *seed* 1)
(define (random-next)
     (let* ((a 16807) (m 2147483647) (q (quotient m a)) (r (modulo m a)))
          (set! *seed*
               (-   (* a (- *seed*
                         (* (quotient *seed* q) q)))
                    (* (quotient *seed* q) r)))
          (if (< *seed* 0) (set! *seed* (+ *seed* m)))
          *seed*))
;; SRFI-0
;; COND-EXPAND
;; Implemented as a macro
(define *features* '(srfi-0))

(define-macro (cond-expand . cond-action-list)
  (cond-expand-runtime cond-action-list))

(define (cond-expand-runtime cond-action-list)
  (if (null? cond-action-list)
      #t
      (if (cond-eval (caar cond-action-list))
          `(begin ,@(cdar cond-action-list))
          (cond-expand-runtime (cdr cond-action-list)))))

(define (cond-eval-and cond-list)
  (foldr (lambda (x y) (and (cond-eval x) (cond-eval y))) #t cond-list))

(define (cond-eval-or cond-list)
  (foldr (lambda (x y) (or (cond-eval x) (cond-eval y))) #f cond-list))

(define (cond-eval condition)
  (cond
    ((symbol? condition)
       (if (member condition *features*) #t #f))
    ((eq? condition #t) #t)
    ((eq? condition #f) #f)
    (else (case (car condition)
            ((and) (cond-eval-and (cdr condition)))
            ((or) (cond-eval-or (cdr condition)))
            ((not) (if (not (null? (cddr condition)))
                     (error "cond-expand : 'not' takes 1 argument")
                     (not (cond-eval (cadr condition)))))
            (else (error "cond-expand : unknown operator" (car condition)))))))

(gc-verbose #f)

-
+ C48269A2C2F362F53C3E68E188B54351006342812EEAEA1CC41418C4CF1BFD0E780CF215AAD11E50FB0C53E1EEF05874121958BEE709E35E131D32B85831BC46
bitcoin/src/shiva/Manual.txt

(0 . 0)(1 . 452)


                       TinySCHEME Version 1.41

                    "Safe if used as prescribed"
                    -- Philip K. Dick, "Ubik"

This software is open source, covered by a BSD-style license.
Please read accompanying file COPYING.
-------------------------------------------------------------------------------

     This Scheme interpreter is based on MiniSCHEME version 0.85k4
     (see miniscm.tar.gz in the Scheme Repository)
     Original credits in file MiniSCHEMETribute.txt.

     D. Souflis (dsouflis@acm.org)

-------------------------------------------------------------------------------
     What is TinyScheme?
     -------------------

     TinyScheme is a lightweight Scheme interpreter that implements as large
     a subset of R5RS as was possible without getting very large and
     complicated. It is meant to be used as an embedded scripting interpreter
     for other programs. As such, it does not offer IDEs or extensive toolkits
     although it does sport a small top-level loop, included conditionally.
     A lot of functionality in TinyScheme is included conditionally, to allow
     developers freedom in balancing features and footprint.

     As an embedded interpreter, it allows multiple interpreter states to
     coexist in the same program, without any interference between them.
     Programmatically, foreign functions in C can be added and values
     can be defined in the Scheme environment. Being a quite small program,
     it is easy to comprehend, get to grips with, and use.

     Known bugs
     ----------

     TinyScheme is known to misbehave when memory is exhausted.


     Things that keep missing, or that need fixing
     ---------------------------------------------

     There are no hygienic macros. No rational or
     complex numbers. No unwind-protect and call-with-values.

     Maybe (a subset of) SLIB will work with TinySCHEME...

     Decent debugging facilities are missing. Only tracing is supported
     natively.


     Scheme Reference
     ----------------

     If something seems to be missing, please refer to the code and
     "init.scm", since some are library functions.  Refer to the MiniSCHEME
     readme as a last resort.

          Environments
     (interaction-environment)
     See R5RS. In TinySCHEME, immutable list of association lists.

     (current-environment)
     The environment in effect at the time of the call. An example of its
     use and its utility can be found in the sample code that implements
     packages in "init.scm":

          (macro (package form)
               `(apply (lambda ()
                         ,@(cdr form)
                         (current-environment))))

     The environment containing the (local) definitions inside the closure
     is returned as an immutable value.

     (defined? <symbol>) (defined? <symbol> <environment>)
     Checks whether the given symbol is defined in the current (or given)
     environment.

          Symbols
     (gensym)
     Returns a new interned symbol each time. Will probably move to the
     library when string->symbol is implemented.

          Directives
     (gc)
     Performs garbage collection immediatelly.

     (gcverbose) (gcverbose <bool>)
     The argument (defaulting to #t) controls whether GC produces
     visible outcome.

     (quit) (quit <num>)
     Stops the interpreter and sets the 'retcode' internal field (defaults
     to 0). When standalone, 'retcode' is returned as exit code to the OS.

     (tracing <num>)
     1, turns on tracing. 0 turns it off. (Only when USE_TRACING is 1).

          Mathematical functions
     Since rationals and complexes are absent, the respective functions
     are also missing.
     Supported: exp, log, sin, cos, tan, asin, acos, atan, floor, ceiling,
     trunc, round and also sqrt and expt when USE_MATH=1.
     Number-theoretical quotient, remainder and modulo, gcd, lcm.
     Library: exact?, inexact?, odd?, even?, zero?, positive?, negative?,
     exact->inexact. inexact->exact is a core function.

          Type predicates
     boolean?,eof-object?,symbol?,number?,string?,integer?,real?,list?,null?,
     char?,port?,input-port?,output-port?,procedure?,pair?,environment?',
     vector?. Also closure?, macro?.

          Types
     Types supported:

          Numbers (integers and reals)
          Symbols
          Pairs
          Strings
          Characters
          Ports
          Eof object
          Environments
          Vectors

          Literals
     String literals can contain escaped quotes \" as usual, but also
     \n, \r, \t, \xDD (hex representations) and \DDD (octal representations).
     Note also that it is possible to include literal newlines in string
     literals, e.g.

          (define s "String with newline here
          and here
          that can function like a HERE-string")

     Character literals contain #\space and #\newline and are supplemented
     with #\return and #\tab, with obvious meanings. Hex character
     representations are allowed (e.g. #\x20 is #\space).
     When USE_ASCII_NAMES is defined, various control characters can be
     referred to by their ASCII name.
     0	     #\nul	       17       #\dc1
     1	     #\soh             18       #\dc2
     2	     #\stx             19       #\dc3
     3	     #\etx             20       #\dc4
     4	     #\eot             21       #\nak
     5	     #\enq             22       #\syn
     6	     #\ack             23       #\etv
     7	     #\bel             24       #\can
     8	     #\bs              25       #\em
     9	     #\ht              26       #\sub
     10	     #\lf              27       #\esc
     11	     #\vt              28       #\fs
     12	     #\ff              29       #\gs
     13	     #\cr              30       #\rs
     14	     #\so              31       #\us
     15	     #\si
     16	     #\dle             127      #\del 		

     Numeric literals support #x #o #b and #d. Flonums are currently read only
     in decimal notation. Full grammar will be supported soon.

          Quote, quasiquote etc.
     As usual.

          Immutable values
     Immutable pairs cannot be modified by set-car! and set-cdr!.
     Immutable strings cannot be modified via string-set!

          I/O
     As per R5RS, plus String Ports (see below).
     current-input-port, current-output-port,
     close-input-port, close-output-port, input-port?, output-port?,
     open-input-file, open-output-file.
     read, write, display, newline, write-char, read-char, peek-char.
     char-ready? returns #t only for string ports, because there is no
     portable way in stdio to determine if a character is available.
     Also open-input-output-file, set-input-port, set-output-port (not R5RS)
     Library: call-with-input-file, call-with-output-file,
     with-input-from-file, with-output-from-file and
     with-input-output-from-to-files, close-port and input-output-port?
     (not R5RS).
     String Ports: open-input-string, open-output-string, get-output-string,
     open-input-output-string. Strings can be used with I/O routines.

          Vectors
     make-vector, vector, vector-length, vector-ref, vector-set!, list->vector,
     vector-fill!, vector->list, vector-equal? (auxiliary function, not R5RS)

          Strings
     string, make-string, list->string, string-length, string-ref, string-set!,
     substring, string->list, string-fill!, string-append, string-copy.
     string=?, string<?, string>?, string>?, string<=?, string>=?.
     (No string-ci*? yet). string->number, number->string. Also atom->string,
     string->atom (not R5RS).

          Symbols
     symbol->string, string->symbol

          Characters
     integer->char, char->integer.
     char=?, char<?, char>?, char<=?, char>=?.
     (No char-ci*?)

          Pairs & Lists
     cons, car, cdr, list, length, map, for-each, foldr, list-tail,
     list-ref, last-pair, reverse, append.
     Also member, memq, memv, based on generic-member, assoc, assq, assv
     based on generic-assoc.

          Streams
     head, tail, cons-stream

          Control features
     Apart from procedure?, also macro? and closure?
     map, for-each, force, delay, call-with-current-continuation (or call/cc),
     eval, apply. 'Forcing' a value that is not a promise produces the value.
     There is no call-with-values, values, nor dynamic-wind. Dynamic-wind in
     the presence of continuations would require support from the abstract
     machine itself.

          Property lists
     TinyScheme inherited from MiniScheme property lists for symbols.
     put, get.

          Dynamically-loaded extensions
     (load-extension <filename without extension>)
     Loads a DLL declaring foreign procedures. On Unix/Linux, one can make use
     of the ld.so.conf file or the LD_RUN_PATH system variable in order to place
     the library in a directory other than the current one. Please refer to the
     appropriate 'man' page.

          Esoteric procedures
     (oblist)
     Returns the oblist, an immutable list of all the symbols.

     (macro-expand <form>)
     Returns the expanded form of the macro call denoted by the argument

     (define-with-return (<procname> <args>...) <body>)
     Like plain 'define', but makes the continuation available as 'return'
     inside the procedure. Handy for imperative programs.

     (new-segment <num>)
     Allocates more memory segments.

     defined?
     See "Environments"

     (get-closure-code <closure>)
     Gets the code as scheme data.

     (make-closure <code> <environment>)
     Makes a new closure in the given environment.

          Obsolete procedures
     (print-width <object>)

     Programmer's Reference
     ----------------------

     The interpreter state is initialized with "scheme_init".
     Custom memory allocation routines can be installed with an alternate
     initialization function: "scheme_init_custom_alloc".
     Files can be loaded with "scheme_load_file". Strings containing Scheme
     code can be loaded with "scheme_load_string". It is a good idea to
     "scheme_load" init.scm before anything else.

     External data for keeping external state (of use to foreign functions)
     can be installed with "scheme_set_external_data".
     Foreign functions are installed with "assign_foreign". Additional
     definitions can be added to the interpreter state, with "scheme_define"
     (this is the way HTTP header data and HTML form data are passed to the
     Scheme script in the Altera SQL Server). If you wish to define the
     foreign function in a specific environment (to enhance modularity),
     use "assign_foreign_env".

     The procedure "scheme_apply0" has been added with persistent scripts in
     mind. Persistent scripts are loaded once, and every time they are needed
     to produce HTTP output, appropriate data are passed through global
     definitions and function "main" is called to do the job. One could
     add easily "scheme_apply1" etc.

     The interpreter state should be deinitialized with "scheme_deinit".

     DLLs containing foreign functions should define a function named
     init_<base-name>. E.g. foo.dll should define init_foo, and bar.so
     should define init_bar. This function should assign_foreign any foreign
     function contained in the DLL.

     The first dynamically loaded extension available for TinyScheme is
     a regular expression library. Although it's by no means an
     established standard, this library is supposed to be installed in
     a directory mirroring its name under the TinyScheme location.


     Foreign Functions
     -----------------

     The user can add foreign functions in C. For example, a function
     that squares its argument:

          pointer square(scheme *sc, pointer args) {
           if(args!=sc->NIL) {
               if(sc->isnumber(sc->pair_car(args))) {
                    double v=sc->rvalue(sc->pair_car(args));
                    return sc->mk_real(sc,v*v);
               }
           }
           return sc->NIL;
          }

   Foreign functions are now defined as closures:

   sc->interface->scheme_define(
        sc,
        sc->global_env,
        sc->interface->mk_symbol(sc,"square"),
        sc->interface->mk_foreign_func(sc, square));


     Foreign functions can use the external data in the "scheme" struct
     to implement any kind of external state.

     External data are set with the following function:
          void scheme_set_external_data(scheme *sc, void *p);

     As of v.1.17, the canonical way for a foreign function in a DLL to
     manipulate Scheme data is using the function pointers in sc->interface.

     Standalone
     ----------

     Usage: tinyscheme -?
     or:    tinyscheme [<file1> <file2> ...]
     followed by
	       -1 <file> [<arg1> <arg2> ...]
	       -c <Scheme commands> [<arg1> <arg2> ...]
     assuming that the executable is named tinyscheme.

     Use - in the place of a filename to denote stdin.
     The -1 flag is meant for #! usage in shell scripts. If you specify
          #! /somewhere/tinyscheme -1
     then tinyscheme will be called to process the file. For example, the
     following script echoes the Scheme list of its arguments.

	       #! /somewhere/tinyscheme -1
	       (display *args*)

     The -c flag permits execution of arbitrary Scheme code.


     Error Handling
     --------------

     Errors are recovered from without damage. The user can install his
     own handler for system errors, by defining *error-hook*. Defining
     to '() gives the default behavior, which is equivalent to "error".
     USE_ERROR_HOOK must be defined.

     A simple exception handling mechanism can be found in "init.scm".
     A new syntactic form is introduced:

          (catch <expr returned exceptionally>
               <expr1> <expr2> ... <exprN>)

     "Catch" establishes a scope spanning multiple call-frames
     until another "catch" is encountered.

     Exceptions are thrown with:

          (throw "message")

     If used outside a (catch ...), reverts to (error "message").

     Example of use:

          (define (foo x) (write x) (newline) (/ x 0))

          (catch (begin (display "Error!\n") 0)
               (write "Before foo ... ")
               (foo 5)
               (write "After foo"))

     The exception mechanism can be used even by system errors, by

          (define *error-hook* throw)

     which makes use of the error hook described above.

     If necessary, the user can devise his own exception mechanism with
     tagged exceptions etc.


     Reader extensions
     -----------------

     When encountering an unknown character after '#', the user-specified
     procedure *sharp-hook* (if any), is called to read the expression.
     This can be used to extend the reader to handle user-defined constants
     or whatever. It should be a procedure without arguments, reading from
     the current input port (which will be the load-port).


     Colon Qualifiers - Packages
     ---------------------------

     When USE_COLON_HOOK=1:
     The lexer now recognizes the construction <qualifier>::<symbol> and
     transforms it in the following manner (T is the transformation function):

          T(<qualifier>::<symbol>) = (*colon-hook* 'T(<symbol>) <qualifier>)

     where <qualifier> is a symbol not containing any double-colons.

     As the definition is recursive, qualifiers can be nested.
     The user can define his own *colon-hook*, to handle qualified names.
     By default, "init.scm" defines *colon-hook* as EVAL. Consequently,
     the qualifier must denote a Scheme environment, such as one returned
     by (interaction-environment). "Init.scm" defines a new syntantic form,
     PACKAGE, as a simple example. It is used like this:

          (define toto
               (package
                    (define foo 1)
                    (define bar +)))

          foo                                     ==>  Error, "foo" undefined
          (eval 'foo)                             ==>  Error, "foo" undefined
          (eval 'foo toto)                        ==>  1
          toto::foo                               ==>  1
          ((eval 'bar toto) 2 (eval 'foo toto))   ==>  3
          (toto::bar 2 toto::foo)                 ==>  3
          (eval (bar 2 foo) toto)                 ==>  3

     If the user installs another package infrastructure, he must define
     a new 'package' procedure or macro to retain compatibility with supplied
     code.

     Note: Older versions used ':' as a qualifier. Unfortunately, the use
     of ':' as a pseudo-qualifier in existing code (i.e. SLIB) essentially
     precludes its use as a real qualifier.

-
+ 1E6959CA3EC52251E162D6C766CAF558F6FC222D337DBBCB313807C0B7F555F508E05865176D3DF5E92C8A2AA94E27529323A8A2E2F4264FDC1256276CF6B63B
bitcoin/src/shiva/MiniSCHEMETribute.txt

(0 . 0)(1 . 88)
     TinyScheme would not exist if it wasn't for MiniScheme. I had just
     written the HTTP server for Ovrimos SQL Server, and I was lamenting the
     lack of a scripting language. Server-side Javascript would have been the
     preferred solution, had there been a Javascript interpreter I could
     lay my hands on. But there weren't. Perl would have been another solution,
     but it was probably ten times bigger that the program it was supposed to
     be embedded in. There would also be thorny licencing issues. 
     
     So, the obvious thing to do was find a trully small interpreter. Forth
     was a language I had once quasi-implemented, but the difficulty of
     handling dynamic data and the weirdness of the language put me off. I then
     looked around for a LISP interpreter, the next thing I knew was easy to
     implement. Alas, the LeLisp I knew from my days in UPMC (Universite Pierre
     et Marie Curie) had given way to Common Lisp, a megalith of a language!
     Then my search lead me to Scheme, a language I knew was very orthogonal
     and clean. When I found Mini-Scheme, a single C file of some 2400 loc, I 
     fell in love with it! What if it lacked floating-point numbers and 
     strings! The rest, as they say, is history.
     
     Below  are the original credits. Don't email Akira KIDA, the address has
     changed.
     
     ---------- Mini-Scheme Interpreter Version 0.85 ----------

                coded by Atsushi Moriwaki (11/5/1989)

            E-MAIL :  moriwaki@kurims.kurims.kyoto-u.ac.jp

               THIS SOFTWARE IS IN THE PUBLIC DOMAIN
               ------------------------------------
 This software is completely free to copy, modify and/or re-distribute.
 But I would appreciate it if you left my name on the code as the author.

  This version has been modified by R.C. Secrist.

  Mini-Scheme is now maintained by Akira KIDA.

  This is a revised and modified version by Akira KIDA.
   current version is 0.85k4 (15 May 1994)

  Please send suggestions, bug reports and/or requests to:
        <SDI00379@niftyserve.or.jp>


     Features compared to MiniSCHEME
     -------------------------------

     All code is now reentrant. Interpreter state is held in a 'scheme'
     struct, and many interpreters can coexist in the same program, possibly
     in different threads. The user can specify user-defined memory allocation
     primitives. (see "Programmer's Reference")

     The reader is more consistent.

     Strings, characters and flonums are supported. (see "Types")

     Files being loaded can be nested up to some depth.

     R5RS I/O is there, plus String Ports. (see "Scheme Reference","I/O")

     Vectors exist.

     As a standalone application, it supports command-line arguments.
     (see "Standalone")

     Running out of memory is now handled.

     The user can add foreign functions in C. (see "Foreign Functions")

     The code has been changed slightly, core functions have been moved
     to the library, behavior has been aligned with R5RS etc.

     Support has been added for user-defined error recovery.
     (see "Error Handling")

     Support has been added for modular programming.
     (see "Colon Qualifiers - Packages")

     To enable this, EVAL has changed internally, and can
     now take two arguments, as per R5RS. Environments are supported.
     (see "Colon Qualifiers - Packages")

     Promises are now evaluated once only.

     (macro (foo form) ...) is now equivalent to (macro foo (lambda(form) ...))

     The reader can be extended using new #-expressions
     (see "Reader extensions")

-
+ 1BBAEF06AB4B1E168A42B4CD74605BDB7D55412544FF177E2CE07CE7AA07A7FD7B8B44CFBA2B7E28DC057FCC8B4CFA0E00ED66DAC30933E909DD13C81A99760B
bitcoin/src/shiva/opdefines.h

(0 . 0)(1 . 195)
    _OP_DEF(opexe_0, "load",                           1,  1,       TST_STRING,                      OP_LOAD             )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_T0LVL            )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_T1LVL            )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_READ_INTERNAL    )
    _OP_DEF(opexe_0, "gensym",                         0,  0,       0,                               OP_GENSYM           )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_VALUEPRINT       )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_EVAL             )
#if USE_TRACING
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_REAL_EVAL        )
#endif
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_E0ARGS           )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_E1ARGS           )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_APPLY            )
#if USE_TRACING
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_REAL_APPLY       )
    _OP_DEF(opexe_0, "tracing",                        1,  1,       TST_NATURAL,                     OP_TRACING          )
#endif
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_DOMACRO          )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_LAMBDA           )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_LAMBDA1          )
    _OP_DEF(opexe_0, "make-closure",                   1,  2,       TST_PAIR TST_ENVIRONMENT,        OP_MKCLOSURE        )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_QUOTE            )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_DEF0             )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_DEF1             )
    _OP_DEF(opexe_0, "defined?",                       1,  2,       TST_SYMBOL TST_ENVIRONMENT,      OP_DEFP             )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_BEGIN            )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_IF0              )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_IF1              )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_SET0             )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_SET1             )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_LET0             )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_LET1             )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_LET2             )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_LET0AST          )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_LET1AST          )
    _OP_DEF(opexe_0, 0,                                0,  0,       0,                               OP_LET2AST          )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_LET0REC          )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_LET1REC          )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_LET2REC          )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_COND0            )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_COND1            )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_DELAY            )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_AND0             )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_AND1             )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_OR0              )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_OR1              )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_C0STREAM         )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_C1STREAM         )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_MACRO0           )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_MACRO1           )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_CASE0            )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_CASE1            )
    _OP_DEF(opexe_1, 0,                                0,  0,       0,                               OP_CASE2            )
    _OP_DEF(opexe_1, "eval",                           1,  2,       TST_ANY TST_ENVIRONMENT,         OP_PEVAL            )
    _OP_DEF(opexe_1, "apply",                          1,  INF_ARG, TST_NONE,                        OP_PAPPLY           )
    _OP_DEF(opexe_1, "call-with-current-continuation", 1,  1,       TST_NONE,                        OP_CONTINUATION     )
#if USE_MATH
    _OP_DEF(opexe_2, "inexact->exact",                 1,  1,       TST_NUMBER,                      OP_INEX2EX          )
    _OP_DEF(opexe_2, "exp",                            1,  1,       TST_NUMBER,                      OP_EXP              )
    _OP_DEF(opexe_2, "log",                            1,  1,       TST_NUMBER,                      OP_LOG              )
    _OP_DEF(opexe_2, "sin",                            1,  1,       TST_NUMBER,                      OP_SIN              )
    _OP_DEF(opexe_2, "cos",                            1,  1,       TST_NUMBER,                      OP_COS              )
    _OP_DEF(opexe_2, "tan",                            1,  1,       TST_NUMBER,                      OP_TAN              )
    _OP_DEF(opexe_2, "asin",                           1,  1,       TST_NUMBER,                      OP_ASIN             )
    _OP_DEF(opexe_2, "acos",                           1,  1,       TST_NUMBER,                      OP_ACOS             )
    _OP_DEF(opexe_2, "atan",                           1,  2,       TST_NUMBER,                      OP_ATAN             )
    _OP_DEF(opexe_2, "sqrt",                           1,  1,       TST_NUMBER,                      OP_SQRT             )
    _OP_DEF(opexe_2, "expt",                           2,  2,       TST_NUMBER,                      OP_EXPT             )
    _OP_DEF(opexe_2, "floor",                          1,  1,       TST_NUMBER,                      OP_FLOOR            )
    _OP_DEF(opexe_2, "ceiling",                        1,  1,       TST_NUMBER,                      OP_CEILING          )
    _OP_DEF(opexe_2, "truncate",                       1,  1,       TST_NUMBER,                      OP_TRUNCATE         )
    _OP_DEF(opexe_2, "round",                          1,  1,       TST_NUMBER,                      OP_ROUND            )
#endif
    _OP_DEF(opexe_2, "+",                              0,  INF_ARG, TST_NUMBER,                      OP_ADD              )
    _OP_DEF(opexe_2, "-",                              1,  INF_ARG, TST_NUMBER,                      OP_SUB              )
    _OP_DEF(opexe_2, "*",                              0,  INF_ARG, TST_NUMBER,                      OP_MUL              )
    _OP_DEF(opexe_2, "/",                              1,  INF_ARG, TST_NUMBER,                      OP_DIV              )
    _OP_DEF(opexe_2, "quotient",                       1,  INF_ARG, TST_INTEGER,                     OP_INTDIV           )
    _OP_DEF(opexe_2, "remainder",                      2,  2,       TST_INTEGER,                     OP_REM              )
    _OP_DEF(opexe_2, "modulo",                         2,  2,       TST_INTEGER,                     OP_MOD              )
    _OP_DEF(opexe_2, "car",                            1,  1,       TST_PAIR,                        OP_CAR              )
    _OP_DEF(opexe_2, "cdr",                            1,  1,       TST_PAIR,                        OP_CDR              )
    _OP_DEF(opexe_2, "cons",                           2,  2,       TST_NONE,                        OP_CONS             )
    _OP_DEF(opexe_2, "set-car!",                       2,  2,       TST_PAIR TST_ANY,                OP_SETCAR           )
    _OP_DEF(opexe_2, "set-cdr!",                       2,  2,       TST_PAIR TST_ANY,                OP_SETCDR           )
    _OP_DEF(opexe_2, "char->integer",                  1,  1,       TST_CHAR,                        OP_CHAR2INT         )
    _OP_DEF(opexe_2, "integer->char",                  1,  1,       TST_NATURAL,                     OP_INT2CHAR         )
    _OP_DEF(opexe_2, "char-upcase",                    1,  1,       TST_CHAR,                        OP_CHARUPCASE       )
    _OP_DEF(opexe_2, "char-downcase",                  1,  1,       TST_CHAR,                        OP_CHARDNCASE       )
    _OP_DEF(opexe_2, "symbol->string",                 1,  1,       TST_SYMBOL,                      OP_SYM2STR          )
    _OP_DEF(opexe_2, "atom->string",                   1,  2,       TST_ANY TST_NATURAL,             OP_ATOM2STR         )
    _OP_DEF(opexe_2, "string->symbol",                 1,  1,       TST_STRING,                      OP_STR2SYM          )
    _OP_DEF(opexe_2, "string->atom",                   1,  2,       TST_STRING TST_NATURAL,          OP_STR2ATOM         )
    _OP_DEF(opexe_2, "make-string",                    1,  2,       TST_NATURAL TST_CHAR,            OP_MKSTRING         )
    _OP_DEF(opexe_2, "string-length",                  1,  1,       TST_STRING,                      OP_STRLEN           )
    _OP_DEF(opexe_2, "string-ref",                     2,  2,       TST_STRING TST_NATURAL,          OP_STRREF           )
    _OP_DEF(opexe_2, "string-set!",                    3,  3,       TST_STRING TST_NATURAL TST_CHAR, OP_STRSET           )
    _OP_DEF(opexe_2, "string-append",                  0,  INF_ARG, TST_STRING,                      OP_STRAPPEND        )
    _OP_DEF(opexe_2, "substring",                      2,  3,       TST_STRING TST_NATURAL,          OP_SUBSTR           )
    _OP_DEF(opexe_2, "vector",                         0,  INF_ARG, TST_NONE,                        OP_VECTOR           )
    _OP_DEF(opexe_2, "make-vector",                    1,  2,       TST_NATURAL TST_ANY,             OP_MKVECTOR         )
    _OP_DEF(opexe_2, "vector-length",                  1,  1,       TST_VECTOR,                      OP_VECLEN           )
    _OP_DEF(opexe_2, "vector-ref",                     2,  2,       TST_VECTOR TST_NATURAL,          OP_VECREF           )
    _OP_DEF(opexe_2, "vector-set!",                    3,  3,       TST_VECTOR TST_NATURAL TST_ANY,  OP_VECSET           )
    _OP_DEF(opexe_3, "not",                            1,  1,       TST_NONE,                        OP_NOT              )
    _OP_DEF(opexe_3, "boolean?",                       1,  1,       TST_NONE,                        OP_BOOLP            )
    _OP_DEF(opexe_3, "eof-object?",                    1,  1,       TST_NONE,                        OP_EOFOBJP          )
    _OP_DEF(opexe_3, "null?",                          1,  1,       TST_NONE,                        OP_NULLP            )
    _OP_DEF(opexe_3, "=",                              2,  INF_ARG, TST_NUMBER,                      OP_NUMEQ            )
    _OP_DEF(opexe_3, "<",                              2,  INF_ARG, TST_NUMBER,                      OP_LESS             )
    _OP_DEF(opexe_3, ">",                              2,  INF_ARG, TST_NUMBER,                      OP_GRE              )
    _OP_DEF(opexe_3, "<=",                             2,  INF_ARG, TST_NUMBER,                      OP_LEQ              )
    _OP_DEF(opexe_3, ">=",                             2,  INF_ARG, TST_NUMBER,                      OP_GEQ              )
    _OP_DEF(opexe_3, "symbol?",                        1,  1,       TST_ANY,                         OP_SYMBOLP          )
    _OP_DEF(opexe_3, "number?",                        1,  1,       TST_ANY,                         OP_NUMBERP          )
    _OP_DEF(opexe_3, "string?",                        1,  1,       TST_ANY,                         OP_STRINGP          )
    _OP_DEF(opexe_3, "integer?",                       1,  1,       TST_ANY,                         OP_INTEGERP         )
    _OP_DEF(opexe_3, "real?",                          1,  1,       TST_ANY,                         OP_REALP            )
    _OP_DEF(opexe_3, "char?",                          1,  1,       TST_ANY,                         OP_CHARP            )
#if USE_CHAR_CLASSIFIERS
    _OP_DEF(opexe_3, "char-alphabetic?",               1,  1,       TST_CHAR,                        OP_CHARAP           )
    _OP_DEF(opexe_3, "char-numeric?",                  1,  1,       TST_CHAR,                        OP_CHARNP           )
    _OP_DEF(opexe_3, "char-whitespace?",               1,  1,       TST_CHAR,                        OP_CHARWP           )
    _OP_DEF(opexe_3, "char-upper-case?",               1,  1,       TST_CHAR,                        OP_CHARUP           )
    _OP_DEF(opexe_3, "char-lower-case?",               1,  1,       TST_CHAR,                        OP_CHARLP           )
#endif
    _OP_DEF(opexe_3, "port?",                          1,  1,       TST_ANY,                         OP_PORTP            )
    _OP_DEF(opexe_3, "input-port?",                    1,  1,       TST_ANY,                         OP_INPORTP          )
    _OP_DEF(opexe_3, "output-port?",                   1,  1,       TST_ANY,                         OP_OUTPORTP         )
    _OP_DEF(opexe_3, "procedure?",                     1,  1,       TST_ANY,                         OP_PROCP            )
    _OP_DEF(opexe_3, "pair?",                          1,  1,       TST_ANY,                         OP_PAIRP            )
    _OP_DEF(opexe_3, "list?",                          1,  1,       TST_ANY,                         OP_LISTP            )
    _OP_DEF(opexe_3, "environment?",                   1,  1,       TST_ANY,                         OP_ENVP             )
    _OP_DEF(opexe_3, "vector?",                        1,  1,       TST_ANY,                         OP_VECTORP          )
    _OP_DEF(opexe_3, "eq?",                            2,  2,       TST_ANY,                         OP_EQ               )
    _OP_DEF(opexe_3, "eqv?",                           2,  2,       TST_ANY,                         OP_EQV              )
    _OP_DEF(opexe_4, "force",                          1,  1,       TST_ANY,                         OP_FORCE            )
    _OP_DEF(opexe_4, 0,                                0,  0,       0,                               OP_SAVE_FORCED      )
    _OP_DEF(opexe_4, "write",                          1,  2,       TST_ANY TST_OUTPORT,             OP_WRITE            )
    _OP_DEF(opexe_4, "write-char",                     1,  2,       TST_CHAR TST_OUTPORT,            OP_WRITE_CHAR       )
    _OP_DEF(opexe_4, "display",                        1,  2,       TST_ANY TST_OUTPORT,             OP_DISPLAY          )
    _OP_DEF(opexe_4, "newline",                        0,  1,       TST_OUTPORT,                     OP_NEWLINE          )
    _OP_DEF(opexe_4, "error",                          1,  INF_ARG, TST_NONE,                        OP_ERR0             )
    _OP_DEF(opexe_4, 0,                                0,  0,       0,                               OP_ERR1             )
    _OP_DEF(opexe_4, "reverse",                        1,  1,       TST_LIST,                        OP_REVERSE          )
    _OP_DEF(opexe_4, "list*",                          1,  INF_ARG, TST_NONE,                        OP_LIST_STAR        )
    _OP_DEF(opexe_4, "append",                         0,  INF_ARG, TST_NONE,                        OP_APPEND           )
#if USE_PLIST
    _OP_DEF(opexe_4, "put",                            3,  3,       TST_NONE,                        OP_PUT              )
    _OP_DEF(opexe_4, "get",                            2,  2,       TST_NONE,                        OP_GET              )
#endif
    _OP_DEF(opexe_4, "quit",                           0,  1,       TST_NUMBER,                      OP_QUIT             )
    _OP_DEF(opexe_4, "gc",                             0,  0,       0,                               OP_GC               )
    _OP_DEF(opexe_4, "gc-verbose",                     0,  1,       TST_NONE,                        OP_GCVERB           )
    _OP_DEF(opexe_4, "new-segment",                    0,  1,       TST_NUMBER,                      OP_NEWSEGMENT       )
    _OP_DEF(opexe_4, "oblist",                         0,  0,       0,                               OP_OBLIST           )
    _OP_DEF(opexe_4, "current-input-port",             0,  0,       0,                               OP_CURR_INPORT      )
    _OP_DEF(opexe_4, "current-output-port",            0,  0,       0,                               OP_CURR_OUTPORT     )
    _OP_DEF(opexe_4, "open-input-file",                1,  1,       TST_STRING,                      OP_OPEN_INFILE      )
    _OP_DEF(opexe_4, "open-output-file",               1,  1,       TST_STRING,                      OP_OPEN_OUTFILE     )
    _OP_DEF(opexe_4, "open-input-output-file",         1,  1,       TST_STRING,                      OP_OPEN_INOUTFILE   )
#if USE_STRING_PORTS
    _OP_DEF(opexe_4, "open-input-string",              1,  1,       TST_STRING,                      OP_OPEN_INSTRING    )
    _OP_DEF(opexe_4, "open-input-output-string",       1,  1,       TST_STRING,                      OP_OPEN_INOUTSTRING )
    _OP_DEF(opexe_4, "open-output-string",             0,  1,       TST_STRING,                      OP_OPEN_OUTSTRING   )
    _OP_DEF(opexe_4, "get-output-string",              1,  1,       TST_OUTPORT,                     OP_GET_OUTSTRING    )
#endif
    _OP_DEF(opexe_4, "close-input-port",               1,  1,       TST_INPORT,                      OP_CLOSE_INPORT     )
    _OP_DEF(opexe_4, "close-output-port",              1,  1,       TST_OUTPORT,                     OP_CLOSE_OUTPORT    )
    _OP_DEF(opexe_4, "interaction-environment",        0,  0,       0,                               OP_INT_ENV          )
    _OP_DEF(opexe_4, "current-environment",            0,  0,       0,                               OP_CURR_ENV         )
    _OP_DEF(opexe_5, "read",                           0,  1,       TST_INPORT,                      OP_READ             )
    _OP_DEF(opexe_5, "read-char",                      0,  1,       TST_INPORT,                      OP_READ_CHAR        )
    _OP_DEF(opexe_5, "peek-char",                      0,  1,       TST_INPORT,                      OP_PEEK_CHAR        )
    _OP_DEF(opexe_5, "char-ready?",                    0,  1,       TST_INPORT,                      OP_CHAR_READY       )
    _OP_DEF(opexe_5, "set-input-port",                 1,  1,       TST_INPORT,                      OP_SET_INPORT       )
    _OP_DEF(opexe_5, "set-output-port",                1,  1,       TST_OUTPORT,                     OP_SET_OUTPORT      )
    _OP_DEF(opexe_5, 0,                                0,  0,       0,                               OP_RDSEXPR          )
    _OP_DEF(opexe_5, 0,                                0,  0,       0,                               OP_RDLIST           )
    _OP_DEF(opexe_5, 0,                                0,  0,       0,                               OP_RDDOT            )
    _OP_DEF(opexe_5, 0,                                0,  0,       0,                               OP_RDQUOTE          )
    _OP_DEF(opexe_5, 0,                                0,  0,       0,                               OP_RDQQUOTE         )
    _OP_DEF(opexe_5, 0,                                0,  0,       0,                               OP_RDQQUOTEVEC      )
    _OP_DEF(opexe_5, 0,                                0,  0,       0,                               OP_RDUNQUOTE        )
    _OP_DEF(opexe_5, 0,                                0,  0,       0,                               OP_RDUQTSP          )
    _OP_DEF(opexe_5, 0,                                0,  0,       0,                               OP_RDVEC            )
    _OP_DEF(opexe_5, 0,                                0,  0,       0,                               OP_P0LIST           )
    _OP_DEF(opexe_5, 0,                                0,  0,       0,                               OP_P1LIST           )
    _OP_DEF(opexe_5, 0,                                0,  0,       0,                               OP_PVECFROM         )
    _OP_DEF(opexe_6, "length",                         1,  1,       TST_LIST,                        OP_LIST_LENGTH      )
    _OP_DEF(opexe_6, "assq",                           2,  2,       TST_NONE,                        OP_ASSQ             )
    _OP_DEF(opexe_6, "get-closure-code",               1,  1,       TST_NONE,                        OP_GET_CLOSURE      )
    _OP_DEF(opexe_6, "closure?",                       1,  1,       TST_NONE,                        OP_CLOSUREP         )
    _OP_DEF(opexe_6, "macro?",                         1,  1,       TST_NONE,                        OP_MACROP           )
#undef _OP_DEF

-
+ B9F2C8885474FD6B4F7D36955799716E68161BE8F8CFCE3640ADE942FE0064A00D64C7DABC3EC36B24797760B99EA6C79D74A8F984DCC3AEAC2EEF183B3ED70B
bitcoin/src/shiva/scheme.c

(0 . 0)(1 . 5023)
/*
    This version de-crudded for therealbitcoin.org.
    Applied interactive REPL fixups for port redirect mode.
 */

/* T I N Y S C H E M E    1 . 4 1
 *   Dimitrios Souflis (dsouflis@acm.org)
 *   Based on MiniScheme (original credits follow)
 * (MINISCM)               coded by Atsushi Moriwaki (11/5/1989)
 * (MINISCM)           E-MAIL :  moriwaki@kurims.kurims.kyoto-u.ac.jp
 * (MINISCM) This version has been modified by R.C. Secrist.
 * (MINISCM)
 * (MINISCM) Mini-Scheme is now maintained by Akira KIDA.
 * (MINISCM)
 * (MINISCM) This is a revised and modified version by Akira KIDA.
 * (MINISCM)    current version is 0.85k4 (15 May 1994)
 *
 */

#define _SCHEME_SOURCE
#include "scheme-knobs.h"
#include "scheme-private.h"

#include <unistd.h>
#include <sys/types.h>

#if USE_MATH
# include <math.h>
#endif

#include <limits.h>
#include <float.h>
#include <ctype.h>

#if USE_STRCASECMP
#include <strings.h>
#define stricmp strcasecmp
#endif

const char* tiny_scheme_version = PACKAGE_VERSION;

/* Used for documentation purposes, to signal functions in 'interface' */
#define INTERFACE

#define TOK_EOF     (-1)
#define TOK_LPAREN  0
#define TOK_RPAREN  1
#define TOK_DOT     2
#define TOK_ATOM    3
#define TOK_QUOTE   4
#define TOK_COMMENT 5
#define TOK_DQUOTE  6
#define TOK_BQUOTE  7
#define TOK_COMMA   8
#define TOK_ATMARK  9
#define TOK_SHARP   10
#define TOK_SHARP_CONST 11
#define TOK_VEC     12

#define BACKQUOTE '`'
#define DELIMITERS  "()\";\f\t\v\n\r "

/*
 *  Basic memory allocation units
 */

#define banner "TinyScheme 1.41"

#include <string.h>
#include <stdlib.h>

#if USE_STRLWR
static const char *strlwr(char *s) {
  const char *p=s;
  while(*s) {
    *s=tolower(*s);
    s++;
  }
  return p;
}
#endif

#ifndef prompt
# define prompt "ts> "
#endif

#ifndef InitFile
# define InitFile "init.scm"
#endif

#ifndef FIRST_CELLSEGS
# define FIRST_CELLSEGS 3
#endif

enum scheme_types {
  T_STRING=1,
  T_NUMBER=2,
  T_SYMBOL=3,
  T_PROC=4,
  T_PAIR=5,
  T_CLOSURE=6,
  T_CONTINUATION=7,
  T_FOREIGN=8,
  T_CHARACTER=9,
  T_PORT=10,
  T_VECTOR=11,
  T_MACRO=12,
  T_PROMISE=13,
  T_ENVIRONMENT=14,
  T_LAST_SYSTEM_TYPE=14
};

/* ADJ is enough slack to align cells in a TYPE_BITS-bit boundary */
#define ADJ 32
#define TYPE_BITS 5
#define T_MASKTYPE      31    /* 0000000000011111 */
#define T_SYNTAX      4096    /* 0001000000000000 */
#define T_IMMUTABLE   8192    /* 0010000000000000 */
#define T_ATOM       16384    /* 0100000000000000 */   /* only for gc */
#define CLRATOM      49151    /* 1011111111111111 */   /* only for gc */
#define MARK         32768    /* 1000000000000000 */
#define UNMARK       32767    /* 0111111111111111 */


static num num_add(num a, num b);
static num num_mul(num a, num b);
static num num_div(num a, num b);
static num num_intdiv(num a, num b);
static num num_sub(num a, num b);
static num num_rem(num a, num b);
static num num_mod(num a, num b);
static int num_eq(num a, num b);
static int num_gt(num a, num b);
static int num_ge(num a, num b);
static int num_lt(num a, num b);
static int num_le(num a, num b);

#if USE_MATH
static double round_per_R5RS(double x);
#endif
static int is_zero_double(double x);
static INLINE int num_is_integer(pointer p) {
  return ((p)->_object._number.is_fixnum);
}

static num num_zero;
static num num_one;

/* macros for cell operations */
#define typeflag(p)      ((p)->_flag)
#define type(p)          (typeflag(p)&T_MASKTYPE)

INTERFACE INLINE int is_string(pointer p)     { return (type(p)==T_STRING); }
#define strvalue(p)      ((p)->_object._string._svalue)
#define strlength(p)        ((p)->_object._string._length)

INTERFACE static int is_list(scheme *sc, pointer p);
INTERFACE INLINE int is_vector(pointer p)    { return (type(p)==T_VECTOR); }
INTERFACE static void fill_vector(pointer vec, pointer obj);
INTERFACE static pointer vector_elem(pointer vec, int ielem);
INTERFACE static pointer set_vector_elem(pointer vec, int ielem, pointer a);
INTERFACE INLINE int is_number(pointer p)    { return (type(p)==T_NUMBER); }
INTERFACE INLINE int is_integer(pointer p) {
  if (!is_number(p))
      return 0;
  if (num_is_integer(p) || (double)ivalue(p) == rvalue(p))
      return 1;
  return 0;
}

INTERFACE INLINE int is_real(pointer p) {
  return is_number(p) && (!(p)->_object._number.is_fixnum);
}

INTERFACE INLINE int is_character(pointer p) { return (type(p)==T_CHARACTER); }
INTERFACE INLINE char *string_value(pointer p) { return strvalue(p); }
INLINE num nvalue(pointer p)       { return ((p)->_object._number); }
INTERFACE long ivalue(pointer p)      { return (num_is_integer(p)?(p)->_object._number.value.ivalue:(long)(p)->_object._number.value.rvalue); }
INTERFACE double rvalue(pointer p)    { return (!num_is_integer(p)?(p)->_object._number.value.rvalue:(double)(p)->_object._number.value.ivalue); }
#define ivalue_unchecked(p)       ((p)->_object._number.value.ivalue)
#define rvalue_unchecked(p)       ((p)->_object._number.value.rvalue)
#define set_num_integer(p)   (p)->_object._number.is_fixnum=1;
#define set_num_real(p)      (p)->_object._number.is_fixnum=0;
INTERFACE  long charvalue(pointer p)  { return ivalue_unchecked(p); }

INTERFACE INLINE int is_port(pointer p)     { return (type(p)==T_PORT); }
INTERFACE INLINE int is_inport(pointer p)  { return is_port(p) && p->_object._port->kind & port_input; }
INTERFACE INLINE int is_outport(pointer p) { return is_port(p) && p->_object._port->kind & port_output; }

INTERFACE INLINE int is_pair(pointer p)     { return (type(p)==T_PAIR); }
#define car(p)           ((p)->_object._cons._car)
#define cdr(p)           ((p)->_object._cons._cdr)
INTERFACE pointer pair_car(pointer p)   { return car(p); }
INTERFACE pointer pair_cdr(pointer p)   { return cdr(p); }
INTERFACE pointer set_car(pointer p, pointer q) { return car(p)=q; }
INTERFACE pointer set_cdr(pointer p, pointer q) { return cdr(p)=q; }

INTERFACE INLINE int is_symbol(pointer p)   { return (type(p)==T_SYMBOL); }
INTERFACE INLINE char *symname(pointer p)   { return strvalue(car(p)); }
#if USE_PLIST
SCHEME_EXPORT INLINE int hasprop(pointer p)     { return (typeflag(p)&T_SYMBOL); }
#define symprop(p)       cdr(p)
#endif

INTERFACE INLINE int is_syntax(pointer p)   { return (typeflag(p)&T_SYNTAX); }
INTERFACE INLINE int is_proc(pointer p)     { return (type(p)==T_PROC); }
INTERFACE INLINE int is_foreign(pointer p)  { return (type(p)==T_FOREIGN); }
INTERFACE INLINE char *syntaxname(pointer p) { return strvalue(car(p)); }
#define procnum(p)       ivalue(p)
static const char *procname(pointer x);

INTERFACE INLINE int is_closure(pointer p)  { return (type(p)==T_CLOSURE); }
INTERFACE INLINE int is_macro(pointer p)    { return (type(p)==T_MACRO); }
INTERFACE INLINE pointer closure_code(pointer p)   { return car(p); }
INTERFACE INLINE pointer closure_env(pointer p)    { return cdr(p); }

INTERFACE INLINE int is_continuation(pointer p)    { return (type(p)==T_CONTINUATION); }
#define cont_dump(p)     cdr(p)

/* To do: promise should be forced ONCE only */
INTERFACE INLINE int is_promise(pointer p)  { return (type(p)==T_PROMISE); }

INTERFACE INLINE int is_environment(pointer p) { return (type(p)==T_ENVIRONMENT); }
#define setenvironment(p)    typeflag(p) = T_ENVIRONMENT

#define is_atom(p)       (typeflag(p)&T_ATOM)
#define setatom(p)       typeflag(p) |= T_ATOM
#define clratom(p)       typeflag(p) &= CLRATOM

#define is_mark(p)       (typeflag(p)&MARK)
#define setmark(p)       typeflag(p) |= MARK
#define clrmark(p)       typeflag(p) &= UNMARK

INTERFACE INLINE int is_immutable(pointer p) { return (typeflag(p)&T_IMMUTABLE); }
/*#define setimmutable(p)  typeflag(p) |= T_IMMUTABLE*/
INTERFACE INLINE void setimmutable(pointer p) { typeflag(p) |= T_IMMUTABLE; }

#define caar(p)          car(car(p))
#define cadr(p)          car(cdr(p))
#define cdar(p)          cdr(car(p))
#define cddr(p)          cdr(cdr(p))
#define cadar(p)         car(cdr(car(p)))
#define caddr(p)         car(cdr(cdr(p)))
#define cdaar(p)         cdr(car(car(p)))
#define cadaar(p)        car(cdr(car(car(p))))
#define cadddr(p)        car(cdr(cdr(cdr(p))))
#define cddddr(p)        cdr(cdr(cdr(cdr(p))))

#if USE_CHAR_CLASSIFIERS
static INLINE int Cisalpha(int c) { return isascii(c) && isalpha(c); }
static INLINE int Cisdigit(int c) { return isascii(c) && isdigit(c); }
static INLINE int Cisspace(int c) { return isascii(c) && isspace(c); }
static INLINE int Cisupper(int c) { return isascii(c) && isupper(c); }
static INLINE int Cislower(int c) { return isascii(c) && islower(c); }
#endif

#if USE_ASCII_NAMES
static const char *charnames[32]={
 "nul",
 "soh",
 "stx",
 "etx",
 "eot",
 "enq",
 "ack",
 "bel",
 "bs",
 "ht",
 "lf",
 "vt",
 "ff",
 "cr",
 "so",
 "si",
 "dle",
 "dc1",
 "dc2",
 "dc3",
 "dc4",
 "nak",
 "syn",
 "etb",
 "can",
 "em",
 "sub",
 "esc",
 "fs",
 "gs",
 "rs",
 "us"
};

static int is_ascii_name(const char *name, int *pc) {
  int i;
  for(i=0; i<32; i++) {
     if(stricmp(name,charnames[i])==0) {
          *pc=i;
          return 1;
     }
  }
  if(stricmp(name,"del")==0) {
     *pc=127;
     return 1;
  }
  return 0;
}

#endif

static int file_push(scheme *sc, const char *fname);
static void file_pop(scheme *sc);
static int file_interactive(scheme *sc);
static INLINE int is_one_of(char *s, int c);
static int alloc_cellseg(scheme *sc, int n);
static long binary_decode(const char *s);
static INLINE pointer get_cell(scheme *sc, pointer a, pointer b);
static pointer _get_cell(scheme *sc, pointer a, pointer b);
static pointer reserve_cells(scheme *sc, int n);
static pointer get_consecutive_cells(scheme *sc, int n);
static pointer find_consecutive_cells(scheme *sc, int n);
static void finalize_cell(scheme *sc, pointer a);
static int count_consecutive_cells(pointer x, int needed);
static pointer find_slot_in_env(scheme *sc, pointer env, pointer sym, int all);
static pointer mk_number(scheme *sc, num n);
static char *store_string(scheme *sc, int len, const char *str, char fill);
static pointer mk_vector(scheme *sc, int len);
static pointer mk_atom(scheme *sc, char *q);
static pointer mk_sharp_const(scheme *sc, char *name);
static pointer mk_port(scheme *sc, port *p);
static pointer port_from_filename(scheme *sc, const char *fn, int prop);
static pointer port_from_file(scheme *sc, FILE *, int prop);
static pointer port_from_string(scheme *sc, char *start, char *past_the_end, int prop);
static port *port_rep_from_filename(scheme *sc, const char *fn, int prop);
static port *port_rep_from_file(scheme *sc, FILE *, int prop);
static port *port_rep_from_string(scheme *sc, char *start, char *past_the_end, int prop);
static void port_close(scheme *sc, pointer p, int flag);
static void mark(pointer a);
static void gc(scheme *sc, pointer a, pointer b);
static int basic_inchar(port *pt);
static int inchar(scheme *sc);
static void backchar(scheme *sc, int c);
static char   *readstr_upto(scheme *sc, char *delim);
static pointer readstrexp(scheme *sc);
static INLINE int skipspace(scheme *sc);
static int token(scheme *sc);
static void printslashstring(scheme *sc, char *s, int len);
static void atom2str(scheme *sc, pointer l, int f, char **pp, int *plen);
static void printatom(scheme *sc, pointer l, int f);
static pointer mk_proc(scheme *sc, enum scheme_opcodes op);
static pointer mk_closure(scheme *sc, pointer c, pointer e);
static pointer mk_continuation(scheme *sc, pointer d);
static pointer reverse(scheme *sc, pointer a);
static pointer reverse_in_place(scheme *sc, pointer term, pointer list);
static pointer revappend(scheme *sc, pointer a, pointer b);
static void dump_stack_mark(scheme *);
static pointer opexe_0(scheme *sc, enum scheme_opcodes op);
static pointer opexe_1(scheme *sc, enum scheme_opcodes op);
static pointer opexe_2(scheme *sc, enum scheme_opcodes op);
static pointer opexe_3(scheme *sc, enum scheme_opcodes op);
static pointer opexe_4(scheme *sc, enum scheme_opcodes op);
static pointer opexe_5(scheme *sc, enum scheme_opcodes op);
static pointer opexe_6(scheme *sc, enum scheme_opcodes op);
static void Eval_Cycle(scheme *sc, enum scheme_opcodes op);
static void assign_syntax(scheme *sc, char *name);
static int syntaxnum(pointer p);
static void assign_proc(scheme *sc, enum scheme_opcodes, char *name);

#define num_ivalue(n)       (n.is_fixnum?(n).value.ivalue:(long)(n).value.rvalue)
#define num_rvalue(n)       (!n.is_fixnum?(n).value.rvalue:(double)(n).value.ivalue)

static num num_add(num a, num b) {
 num ret;
 ret.is_fixnum=a.is_fixnum && b.is_fixnum;
 if(ret.is_fixnum) {
     ret.value.ivalue= a.value.ivalue+b.value.ivalue;
 } else {
     ret.value.rvalue=num_rvalue(a)+num_rvalue(b);
 }
 return ret;
}

static num num_mul(num a, num b) {
 num ret;
 ret.is_fixnum=a.is_fixnum && b.is_fixnum;
 if(ret.is_fixnum) {
     ret.value.ivalue= a.value.ivalue*b.value.ivalue;
 } else {
     ret.value.rvalue=num_rvalue(a)*num_rvalue(b);
 }
 return ret;
}

static num num_div(num a, num b) {
 num ret;
 ret.is_fixnum=a.is_fixnum && b.is_fixnum && a.value.ivalue%b.value.ivalue==0;
 if(ret.is_fixnum) {
     ret.value.ivalue= a.value.ivalue/b.value.ivalue;
 } else {
     ret.value.rvalue=num_rvalue(a)/num_rvalue(b);
 }
 return ret;
}

static num num_intdiv(num a, num b) {
 num ret;
 ret.is_fixnum=a.is_fixnum && b.is_fixnum;
 if(ret.is_fixnum) {
     ret.value.ivalue= a.value.ivalue/b.value.ivalue;
 } else {
     ret.value.rvalue=num_rvalue(a)/num_rvalue(b);
 }
 return ret;
}

static num num_sub(num a, num b) {
 num ret;
 ret.is_fixnum=a.is_fixnum && b.is_fixnum;
 if(ret.is_fixnum) {
     ret.value.ivalue= a.value.ivalue-b.value.ivalue;
 } else {
     ret.value.rvalue=num_rvalue(a)-num_rvalue(b);
 }
 return ret;
}

static num num_rem(num a, num b) {
 num ret;
 long e1, e2, res;
 ret.is_fixnum=a.is_fixnum && b.is_fixnum;
 e1=num_ivalue(a);
 e2=num_ivalue(b);
 res=e1%e2;
 /* remainder should have same sign as second operand */
 if (res > 0) {
     if (e1 < 0) {
        res -= labs(e2);
     }
 } else if (res < 0) {
     if (e1 > 0) {
         res += labs(e2);
     }
 }
 ret.value.ivalue=res;
 return ret;
}

static num num_mod(num a, num b) {
 num ret;
 long e1, e2, res;
 ret.is_fixnum=a.is_fixnum && b.is_fixnum;
 e1=num_ivalue(a);
 e2=num_ivalue(b);
 res=e1%e2;
 /* modulo should have same sign as second operand */
 if (res * e2 < 0) {
    res += e2;
 }
 ret.value.ivalue=res;
 return ret;
}

static int num_eq(num a, num b) {
 int ret;
 int is_fixnum=a.is_fixnum && b.is_fixnum;
 if(is_fixnum) {
     ret= a.value.ivalue==b.value.ivalue;
 } else {
     ret=num_rvalue(a)==num_rvalue(b);
 }
 return ret;
}


static int num_gt(num a, num b) {
 int ret;
 int is_fixnum=a.is_fixnum && b.is_fixnum;
 if(is_fixnum) {
     ret= a.value.ivalue>b.value.ivalue;
 } else {
     ret=num_rvalue(a)>num_rvalue(b);
 }
 return ret;
}

static int num_ge(num a, num b) {
 return !num_lt(a,b);
}

static int num_lt(num a, num b) {
 int ret;
 int is_fixnum=a.is_fixnum && b.is_fixnum;
 if(is_fixnum) {
     ret= a.value.ivalue<b.value.ivalue;
 } else {
     ret=num_rvalue(a)<num_rvalue(b);
 }
 return ret;
}

static int num_le(num a, num b) {
 return !num_gt(a,b);
}

#if USE_MATH
/* Round to nearest. Round to even if midway */
static double round_per_R5RS(double x) {
 double fl=floor(x);
 double ce=ceil(x);
 double dfl=x-fl;
 double dce=ce-x;
 if(dfl>dce) {
     return ce;
 } else if(dfl<dce) {
     return fl;
 } else {
     if(fmod(fl,2.0)==0.0) {       /* I imagine this holds */
          return fl;
     } else {
          return ce;
     }
 }
}
#endif

static int is_zero_double(double x) {
 return x<DBL_MIN && x>-DBL_MIN;
}

static long binary_decode(const char *s) {
 long x=0;

 while(*s!=0 && (*s=='1' || *s=='0')) {
     x<<=1;
     x+=*s-'0';
     s++;
 }

 return x;
}

/* allocate new cell segment */
static int alloc_cellseg(scheme *sc, int n) {
     pointer newp;
     pointer last;
     pointer p;
     char *cp;
     long i;
     int k;
     int adj=ADJ;

     if(adj<sizeof(struct cell)) {
       adj=sizeof(struct cell);
     }

     for (k = 0; k < n; k++) {
         if (sc->last_cell_seg >= CELL_NSEGMENT - 1)
              return k;
         cp = (char*) sc->malloc(CELL_SEGSIZE * sizeof(struct cell)+adj);
         if (cp == 0)
              return k;
         i = ++sc->last_cell_seg ;
         sc->alloc_seg[i] = cp;
         /* adjust in TYPE_BITS-bit boundary */
         if(((unsigned long)cp)%adj!=0) {
           cp=(char*)(adj*((unsigned long)cp/adj+1));
         }
         /* insert new segment in address order */
         newp=(pointer)cp;
         sc->cell_seg[i] = newp;
         while (i > 0 && sc->cell_seg[i - 1] > sc->cell_seg[i]) {
             p = sc->cell_seg[i];
             sc->cell_seg[i] = sc->cell_seg[i - 1];
             sc->cell_seg[--i] = p;
         }
         sc->fcells += CELL_SEGSIZE;
         last = newp + CELL_SEGSIZE - 1;
         for (p = newp; p <= last; p++) {
              typeflag(p) = 0;
              cdr(p) = p + 1;
              car(p) = sc->NIL;
         }
         /* insert new cells in address order on free list */
         if (sc->free_cell == sc->NIL || p < sc->free_cell) {
              cdr(last) = sc->free_cell;
              sc->free_cell = newp;
         } else {
               p = sc->free_cell;
               while (cdr(p) != sc->NIL && newp > cdr(p))
                    p = cdr(p);
               cdr(last) = cdr(p);
               cdr(p) = newp;
         }
     }
     return n;
}

static INLINE pointer get_cell_x(scheme *sc, pointer a, pointer b) {
  if (sc->free_cell != sc->NIL) {
    pointer x = sc->free_cell;
    sc->free_cell = cdr(x);
    --sc->fcells;
    return (x);
  }
  return _get_cell (sc, a, b);
}


/* get new cell.  parameter a, b is marked by gc. */
static pointer _get_cell(scheme *sc, pointer a, pointer b) {
  pointer x;

  if(sc->no_memory) {
    return sc->sink;
  }

  if (sc->free_cell == sc->NIL) {
    const int min_to_be_recovered = sc->last_cell_seg*8;
    gc(sc,a, b);
    if (sc->fcells < min_to_be_recovered
        || sc->free_cell == sc->NIL) {
      /* if only a few recovered, get more to avoid fruitless gc's */
      if (!alloc_cellseg(sc,1) && sc->free_cell == sc->NIL) {
        sc->no_memory=1;
        return sc->sink;
      }
    }
  }
  x = sc->free_cell;
  sc->free_cell = cdr(x);
  --sc->fcells;
  return (x);
}

/* make sure that there is a given number of cells free */
static pointer reserve_cells(scheme *sc, int n) {
    if(sc->no_memory) {
        return sc->NIL;
    }

    /* Are there enough cells available? */
    if (sc->fcells < n) {
        /* If not, try gc'ing some */
        gc(sc, sc->NIL, sc->NIL);
        if (sc->fcells < n) {
            /* If there still aren't, try getting more heap */
            if (!alloc_cellseg(sc,1)) {
                sc->no_memory=1;
                return sc->NIL;
            }
        }
        if (sc->fcells < n) {
            /* If all fail, report failure */
            sc->no_memory=1;
            return sc->NIL;
        }
    }
    return (sc->T);
}

static pointer get_consecutive_cells(scheme *sc, int n) {
  pointer x;

  if(sc->no_memory) { return sc->sink; }

  /* Are there any cells available? */
  x=find_consecutive_cells(sc,n);
  if (x != sc->NIL) { return x; }

  /* If not, try gc'ing some */
  gc(sc, sc->NIL, sc->NIL);
  x=find_consecutive_cells(sc,n);
  if (x != sc->NIL) { return x; }

  /* If there still aren't, try getting more heap */
  if (!alloc_cellseg(sc,1))
    {
      sc->no_memory=1;
      return sc->sink;
    }

  x=find_consecutive_cells(sc,n);
  if (x != sc->NIL) { return x; }

  /* If all fail, report failure */
  sc->no_memory=1;
  return sc->sink;
}

static int count_consecutive_cells(pointer x, int needed) {
 int n=1;
 while(cdr(x)==x+1) {
     x=cdr(x);
     n++;
     if(n>needed) return n;
 }
 return n;
}

static pointer find_consecutive_cells(scheme *sc, int n) {
  pointer *pp;
  int cnt;

  pp=&sc->free_cell;
  while(*pp!=sc->NIL) {
    cnt=count_consecutive_cells(*pp,n);
    if(cnt>=n) {
      pointer x=*pp;
      *pp=cdr(*pp+n-1);
      sc->fcells -= n;
      return x;
    }
    pp=&cdr(*pp+cnt-1);
  }
  return sc->NIL;
}

/* To retain recent allocs before interpreter knows about them -
   Tehom */

static void push_recent_alloc(scheme *sc, pointer recent, pointer extra)
{
  pointer holder = get_cell_x(sc, recent, extra);
  typeflag(holder) = T_PAIR | T_IMMUTABLE;
  car(holder) = recent;
  cdr(holder) = car(sc->sink);
  car(sc->sink) = holder;
}


static pointer get_cell(scheme *sc, pointer a, pointer b)
{
  pointer cell   = get_cell_x(sc, a, b);
  /* For right now, include "a" and "b" in "cell" so that gc doesn't
     think they are garbage. */
  /* Tentatively record it as a pair so gc understands it. */
  typeflag(cell) = T_PAIR;
  car(cell) = a;
  cdr(cell) = b;
  push_recent_alloc(sc, cell, sc->NIL);
  return cell;
}

static pointer get_vector_object(scheme *sc, int len, pointer init)
{
  pointer cells = get_consecutive_cells(sc,len/2+len%2+1);
  if(sc->no_memory) { return sc->sink; }
  /* Record it as a vector so that gc understands it. */
  typeflag(cells) = (T_VECTOR | T_ATOM);
  ivalue_unchecked(cells)=len;
  set_num_integer(cells);
  fill_vector(cells,init);
  push_recent_alloc(sc, cells, sc->NIL);
  return cells;
}

static INLINE void ok_to_freely_gc(scheme *sc)
{
  car(sc->sink) = sc->NIL;
}


#if defined TSGRIND
static void check_cell_alloced(pointer p, int expect_alloced)
{
  /* Can't use putstr(sc,str) because callers have no access to
     sc.  */
  if(typeflag(p) & !expect_alloced)
    {
      fprintf(stderr,"Cell is already allocated!\n");
    }
  if(!(typeflag(p)) & expect_alloced)
    {
      fprintf(stderr,"Cell is not allocated!\n");
    }

}
static void check_range_alloced(pointer p, int n, int expect_alloced)
{
  int i;
  for(i = 0;i<n;i++)
    { (void)check_cell_alloced(p+i,expect_alloced); }
}

#endif

/* Medium level cell allocation */

/* get new cons cell */
pointer _cons(scheme *sc, pointer a, pointer b, int immutable) {
  pointer x = get_cell(sc,a, b);

  typeflag(x) = T_PAIR;
  if(immutable) {
    setimmutable(x);
  }
  car(x) = a;
  cdr(x) = b;
  return (x);
}

/* ========== oblist implementation  ========== */

#ifndef USE_OBJECT_LIST

static int hash_fn(const char *key, int table_size);

static pointer oblist_initial_value(scheme *sc)
{
  return mk_vector(sc, 461); /* probably should be bigger */
}

/* returns the new symbol */
static pointer oblist_add_by_name(scheme *sc, const char *name)
{
  pointer x;
  int location;

  x = immutable_cons(sc, mk_string(sc, name), sc->NIL);
  typeflag(x) = T_SYMBOL;
  setimmutable(car(x));

  location = hash_fn(name, ivalue_unchecked(sc->oblist));
  set_vector_elem(sc->oblist, location,
                  immutable_cons(sc, x, vector_elem(sc->oblist, location)));
  return x;
}

static INLINE pointer oblist_find_by_name(scheme *sc, const char *name)
{
  int location;
  pointer x;
  char *s;

  location = hash_fn(name, ivalue_unchecked(sc->oblist));
  for (x = vector_elem(sc->oblist, location); x != sc->NIL; x = cdr(x)) {
    s = symname(car(x));
    /* case-insensitive, per R5RS section 2. */
    if(stricmp(name, s) == 0) {
      return car(x);
    }
  }
  return sc->NIL;
}

static pointer oblist_all_symbols(scheme *sc)
{
  int i;
  pointer x;
  pointer ob_list = sc->NIL;

  for (i = 0; i < ivalue_unchecked(sc->oblist); i++) {
    for (x  = vector_elem(sc->oblist, i); x != sc->NIL; x = cdr(x)) {
      ob_list = cons(sc, x, ob_list);
    }
  }
  return ob_list;
}

#else

static pointer oblist_initial_value(scheme *sc)
{
  return sc->NIL;
}

static INLINE pointer oblist_find_by_name(scheme *sc, const char *name)
{
     pointer x;
     char    *s;

     for (x = sc->oblist; x != sc->NIL; x = cdr(x)) {
        s = symname(car(x));
        /* case-insensitive, per R5RS section 2. */
        if(stricmp(name, s) == 0) {
          return car(x);
        }
     }
     return sc->NIL;
}

/* returns the new symbol */
static pointer oblist_add_by_name(scheme *sc, const char *name)
{
  pointer x;

  x = immutable_cons(sc, mk_string(sc, name), sc->NIL);
  typeflag(x) = T_SYMBOL;
  setimmutable(car(x));
  sc->oblist = immutable_cons(sc, x, sc->oblist);
  return x;
}
static pointer oblist_all_symbols(scheme *sc)
{
  return sc->oblist;
}

#endif

static pointer mk_port(scheme *sc, port *p) {
  pointer x = get_cell(sc, sc->NIL, sc->NIL);

  typeflag(x) = T_PORT|T_ATOM;
  x->_object._port=p;
  return (x);
}

pointer mk_foreign_func(scheme *sc, foreign_func f) {
  pointer x = get_cell(sc, sc->NIL, sc->NIL);

  typeflag(x) = (T_FOREIGN | T_ATOM);
  x->_object._ff=f;
  return (x);
}

INTERFACE pointer mk_character(scheme *sc, int c) {
  pointer x = get_cell(sc,sc->NIL, sc->NIL);

  typeflag(x) = (T_CHARACTER | T_ATOM);
  ivalue_unchecked(x)= c;
  set_num_integer(x);
  return (x);
}

/* get number atom (integer) */
INTERFACE pointer mk_integer(scheme *sc, long num) {
  pointer x = get_cell(sc,sc->NIL, sc->NIL);

  typeflag(x) = (T_NUMBER | T_ATOM);
  ivalue_unchecked(x)= num;
  set_num_integer(x);
  return (x);
}

INTERFACE pointer mk_real(scheme *sc, double n) {
  pointer x = get_cell(sc,sc->NIL, sc->NIL);

  typeflag(x) = (T_NUMBER | T_ATOM);
  rvalue_unchecked(x)= n;
  set_num_real(x);
  return (x);
}

static pointer mk_number(scheme *sc, num n) {
 if(n.is_fixnum) {
     return mk_integer(sc,n.value.ivalue);
 } else {
     return mk_real(sc,n.value.rvalue);
 }
}

/* allocate name to string area */
static char *store_string(scheme *sc, int len_str, const char *str, char fill) {
     char *q;

     q=(char*)sc->malloc(len_str+1);
     if(q==0) {
          sc->no_memory=1;
          return sc->strbuff;
     }
     if(str!=0) {
          snprintf(q, len_str+1, "%s", str);
     } else {
          memset(q, fill, len_str);
          q[len_str]=0;
     }
     return (q);
}

/* get new string */
INTERFACE pointer mk_string(scheme *sc, const char *str) {
     return mk_counted_string(sc,str,strlen(str));
}

INTERFACE pointer mk_counted_string(scheme *sc, const char *str, int len) {
     pointer x = get_cell(sc, sc->NIL, sc->NIL);
     typeflag(x) = (T_STRING | T_ATOM);
     strvalue(x) = store_string(sc,len,str,0);
     strlength(x) = len;
     return (x);
}

INTERFACE pointer mk_empty_string(scheme *sc, int len, char fill) {
     pointer x = get_cell(sc, sc->NIL, sc->NIL);
     typeflag(x) = (T_STRING | T_ATOM);
     strvalue(x) = store_string(sc,len,0,fill);
     strlength(x) = len;
     return (x);
}

INTERFACE static pointer mk_vector(scheme *sc, int len)
{ return get_vector_object(sc,len,sc->NIL); }

INTERFACE static void fill_vector(pointer vec, pointer obj) {
     int i;
     int num=ivalue(vec)/2+ivalue(vec)%2;
     for(i=0; i<num; i++) {
          typeflag(vec+1+i) = T_PAIR;
          setimmutable(vec+1+i);
          car(vec+1+i)=obj;
          cdr(vec+1+i)=obj;
     }
}

INTERFACE static pointer vector_elem(pointer vec, int ielem) {
     int n=ielem/2;
     if(ielem%2==0) {
          return car(vec+1+n);
     } else {
          return cdr(vec+1+n);
     }
}

INTERFACE static pointer set_vector_elem(pointer vec, int ielem, pointer a) {
     int n=ielem/2;
     if(ielem%2==0) {
          return car(vec+1+n)=a;
     } else {
          return cdr(vec+1+n)=a;
     }
}

/* get new symbol */
INTERFACE pointer mk_symbol(scheme *sc, const char *name) {
     pointer x;

     /* first check oblist */
     x = oblist_find_by_name(sc, name);
     if (x != sc->NIL) {
          return (x);
     } else {
          x = oblist_add_by_name(sc, name);
          return (x);
     }
}

INTERFACE pointer gensym(scheme *sc) {
     pointer x;
     char name[40];

     for(; sc->gensym_cnt<LONG_MAX; sc->gensym_cnt++) {
          snprintf(name,40,"gensym-%ld",sc->gensym_cnt);

          /* first check oblist */
          x = oblist_find_by_name(sc, name);

          if (x != sc->NIL) {
               continue;
          } else {
               x = oblist_add_by_name(sc, name);
               return (x);
          }
     }

     return sc->NIL;
}

/* make symbol or number atom from string */
static pointer mk_atom(scheme *sc, char *q) {
     char    c, *p;
     int has_dec_point=0;
     int has_fp_exp = 0;

#if USE_COLON_HOOK
     if((p=strstr(q,"::"))!=0) {
          *p=0;
          return cons(sc, sc->COLON_HOOK,
                          cons(sc,
                              cons(sc,
                                   sc->QUOTE,
                                   cons(sc, mk_atom(sc,p+2), sc->NIL)),
                              cons(sc, mk_symbol(sc,strlwr(q)), sc->NIL)));
     }
#endif

     p = q;
     c = *p++;
     if ((c == '+') || (c == '-')) {
       c = *p++;
       if (c == '.') {
         has_dec_point=1;
         c = *p++;
       }
       if (!isdigit(c)) {
         return (mk_symbol(sc, strlwr(q)));
       }
     } else if (c == '.') {
       has_dec_point=1;
       c = *p++;
       if (!isdigit(c)) {
         return (mk_symbol(sc, strlwr(q)));
       }
     } else if (!isdigit(c)) {
       return (mk_symbol(sc, strlwr(q)));
     }

     for ( ; (c = *p) != 0; ++p) {
          if (!isdigit(c)) {
               if(c=='.') {
                    if(!has_dec_point) {
                         has_dec_point=1;
                         continue;
                    }
               }
               else if ((c == 'e') || (c == 'E')) {
                       if(!has_fp_exp) {
                          has_dec_point = 1; /* decimal point illegal
                                                from now on */
                          p++;
                          if ((*p == '-') || (*p == '+') || isdigit(*p)) {
                             continue;
                          }
                       }
               }
               return (mk_symbol(sc, strlwr(q)));
          }
     }
     if(has_dec_point) {
          return mk_real(sc,atof(q));
     }
     return (mk_integer(sc, atol(q)));
}

/* make constant */
static pointer mk_sharp_const(scheme *sc, char *name) {
     long    x;
     char    tmp[STRBUFFSIZE];

     if (!strcmp(name, "t"))
          return (sc->T);
     else if (!strcmp(name, "f"))
          return (sc->F);
     else if (*name == 'o') {/* #o (octal) */
          snprintf(tmp, STRBUFFSIZE, "0%s", name+1);
          sscanf(tmp, "%lo", (long unsigned *)&x);
          return (mk_integer(sc, x));
     } else if (*name == 'd') {    /* #d (decimal) */
          sscanf(name+1, "%ld", (long int *)&x);
          return (mk_integer(sc, x));
     } else if (*name == 'x') {    /* #x (hex) */
          snprintf(tmp, STRBUFFSIZE, "0x%s", name+1);
          sscanf(tmp, "%lx", (long unsigned *)&x);
          return (mk_integer(sc, x));
     } else if (*name == 'b') {    /* #b (binary) */
          x = binary_decode(name+1);
          return (mk_integer(sc, x));
     } else if (*name == '\\') { /* #\w (character) */
          int c=0;
          if(stricmp(name+1,"space")==0) {
               c=' ';
          } else if(stricmp(name+1,"newline")==0) {
               c='\n';
          } else if(stricmp(name+1,"return")==0) {
               c='\r';
          } else if(stricmp(name+1,"tab")==0) {
               c='\t';
     } else if(name[1]=='x' && name[2]!=0) {
          int c1=0;
          if(sscanf(name+2,"%x",(unsigned int *)&c1)==1 && c1 < UCHAR_MAX) {
               c=c1;
          } else {
               return sc->NIL;
     }
#if USE_ASCII_NAMES
          } else if(is_ascii_name(name+1,&c)) {
               /* nothing */
#endif
          } else if(name[2]==0) {
               c=name[1];
          } else {
               return sc->NIL;
          }
          return mk_character(sc,c);
     } else
          return (sc->NIL);
}

/* ========== garbage collector ========== */

/*--
 *  We use algorithm E (Knuth, The Art of Computer Programming Vol.1,
 *  sec. 2.3.5), the Schorr-Deutsch-Waite link-inversion algorithm,
 *  for marking.
 */
static void mark(pointer a) {
     pointer t, q, p;

     t = (pointer) 0;
     p = a;
E2:  setmark(p);
     if(is_vector(p)) {
          int i;
          int num=ivalue_unchecked(p)/2+ivalue_unchecked(p)%2;
          for(i=0; i<num; i++) {
               /* Vector cells will be treated like ordinary cells */
               mark(p+1+i);
          }
     }
     if (is_atom(p))
          goto E6;
     /* E4: down car */
     q = car(p);
     if (q && !is_mark(q)) {
          setatom(p);  /* a note that we have moved car */
          car(p) = t;
          t = p;
          p = q;
          goto E2;
     }
E5:  q = cdr(p); /* down cdr */
     if (q && !is_mark(q)) {
          cdr(p) = t;
          t = p;
          p = q;
          goto E2;
     }
E6:   /* up.  Undo the link switching from steps E4 and E5. */
     if (!t)
          return;
     q = t;
     if (is_atom(q)) {
          clratom(q);
          t = car(q);
          car(q) = p;
          p = q;
          goto E5;
     } else {
          t = cdr(q);
          cdr(q) = p;
          p = q;
          goto E6;
     }
}

/* garbage collection. parameter a, b is marked. */
static void gc(scheme *sc, pointer a, pointer b) {
  pointer p;
  int i;

  if(sc->gc_verbose) {
    putstr(sc, "gc...");
  }

  /* mark system globals */
  mark(sc->oblist);
  mark(sc->global_env);

  /* mark current registers */
  mark(sc->args);
  mark(sc->envir);
  mark(sc->code);
  dump_stack_mark(sc);
  mark(sc->value);
  mark(sc->inport);
  mark(sc->save_inport);
  mark(sc->outport);
  mark(sc->loadport);

  /* Mark recent objects the interpreter doesn't know about yet. */
  mark(car(sc->sink));
  /* Mark any older stuff above nested C calls */
  mark(sc->c_nest);

  /* mark variables a, b */
  mark(a);
  mark(b);

  /* garbage collect */
  clrmark(sc->NIL);
  sc->fcells = 0;
  sc->free_cell = sc->NIL;
  /* free-list is kept sorted by address so as to maintain consecutive
     ranges, if possible, for use with vectors. Here we scan the cells
     (which are also kept sorted by address) downwards to build the
     free-list in sorted order.
  */
  for (i = sc->last_cell_seg; i >= 0; i--) {
    p = sc->cell_seg[i] + CELL_SEGSIZE;
    while (--p >= sc->cell_seg[i]) {
      if (is_mark(p)) {
    clrmark(p);
      } else {
    /* reclaim cell */
        if (typeflag(p) != 0) {
          finalize_cell(sc, p);
          typeflag(p) = 0;
          car(p) = sc->NIL;
        }
        ++sc->fcells;
        cdr(p) = sc->free_cell;
        sc->free_cell = p;
      }
    }
  }

  if (sc->gc_verbose) {
    char msg[80];
    snprintf(msg,80,"done: %ld cells were recovered.\n", sc->fcells);
    putstr(sc,msg);
  }
}

static void finalize_cell(scheme *sc, pointer a) {
  if(is_string(a)) {
    sc->free(strvalue(a));
  } else if(is_port(a)) {
    if(a->_object._port->kind&port_file
       && a->_object._port->rep.stdio.closeit) {
      port_close(sc,a,port_input|port_output);
    }
    sc->free(a->_object._port);
  }
}

/* ========== Routines for Reading ========== */

static int file_push(scheme *sc, const char *fname) {
  FILE *fin = NULL;

  if (sc->file_i == MAXFIL-1)
     return 0;
  fin=fopen(fname,"r");
  if(fin!=0) {
    sc->file_i++;
    sc->load_stack[sc->file_i].kind=port_file|port_input;
    sc->load_stack[sc->file_i].rep.stdio.file=fin;
    sc->load_stack[sc->file_i].rep.stdio.closeit=1;
    sc->nesting_stack[sc->file_i]=0;
    sc->loadport->_object._port=sc->load_stack+sc->file_i;

#if SHOW_ERROR_LINE
    sc->load_stack[sc->file_i].rep.stdio.curr_line = 0;
    if(fname)
      sc->load_stack[sc->file_i].rep.stdio.filename = store_string(sc, strlen(fname), fname, 0);
#endif
  }
  return fin!=0;
}

static void file_pop(scheme *sc) {
 if(sc->file_i != 0) {
   sc->nesting=sc->nesting_stack[sc->file_i];
   port_close(sc,sc->loadport,port_input);
   sc->file_i--;
   sc->loadport->_object._port=sc->load_stack+sc->file_i;
 }
}

static int file_interactive(scheme *sc) {
 return sc->file_i==0 && sc->load_stack[0].rep.stdio.interactive /* sc->load_stack[0].rep.stdio.file==stdin */
     && sc->inport->_object._port->kind&port_file;
}

static port *port_rep_from_filename(scheme *sc, const char *fn, int prop) {
  FILE *f;
  char *rw;
  port *pt;
  if(prop==(port_input|port_output)) {
    rw="a+";
  } else if(prop==port_output) {
    rw="w";
  } else {
    rw="r";
  }
  f=fopen(fn,rw);
  if(f==0) {
    return 0;
  }
  pt=port_rep_from_file(sc,f,prop);
  pt->rep.stdio.closeit=1;
  pt->rep.stdio.interactive=0;

#if SHOW_ERROR_LINE
  if(fn)
    pt->rep.stdio.filename = store_string(sc, strlen(fn), fn, 0);

  pt->rep.stdio.curr_line = 0;
#endif
  return pt;
}

static pointer port_from_filename(scheme *sc, const char *fn, int prop) {
  port *pt;
  pt=port_rep_from_filename(sc,fn,prop);
  if(pt==0) {
    return sc->NIL;
  }
  return mk_port(sc,pt);
}

static port *port_rep_from_file(scheme *sc, FILE *f, int prop)
{
    port *pt;

    pt = (port *)sc->malloc(sizeof *pt);
    if (pt == NULL) {
        return NULL;
    }
    pt->kind = port_file | prop;
    pt->rep.stdio.file = f;
    pt->rep.stdio.closeit = 0;
    pt->rep.stdio.interactive=sc->interactive_repl;
    return pt;
}

static pointer port_from_file(scheme *sc, FILE *f, int prop) {
  port *pt;
  pt=port_rep_from_file(sc,f,prop);
  if(pt==0) {
    return sc->NIL;
  }
  return mk_port(sc,pt);
}

static port *port_rep_from_string(scheme *sc, char *start, char *past_the_end, int prop) {
  port *pt;
  pt=(port*)sc->malloc(sizeof(port));
  if(pt==0) {
    return 0;
  }
  pt->kind=port_string|prop;
  pt->rep.string.start=start;
  pt->rep.string.curr=start;
  pt->rep.string.past_the_end=past_the_end;
  return pt;
}

static pointer port_from_string(scheme *sc, char *start, char *past_the_end, int prop) {
  port *pt;
  pt=port_rep_from_string(sc,start,past_the_end,prop);
  if(pt==0) {
    return sc->NIL;
  }
  return mk_port(sc,pt);
}

#define BLOCK_SIZE 256

static port *port_rep_from_scratch(scheme *sc) {
  port *pt;
  char *start;
  pt=(port*)sc->malloc(sizeof(port));
  if(pt==0) {
    return 0;
  }
  start=sc->malloc(BLOCK_SIZE);
  if(start==0) {
    return 0;
  }
  memset(start,' ',BLOCK_SIZE-1);
  start[BLOCK_SIZE-1]='\0';
  pt->kind=port_string|port_output|port_srfi6;
  pt->rep.string.start=start;
  pt->rep.string.curr=start;
  pt->rep.string.past_the_end=start+BLOCK_SIZE-1;
  return pt;
}

static pointer port_from_scratch(scheme *sc) {
  port *pt;
  pt=port_rep_from_scratch(sc);
  if(pt==0) {
    return sc->NIL;
  }
  return mk_port(sc,pt);
}

static void port_close(scheme *sc, pointer p, int flag) {
  port *pt=p->_object._port;
  pt->kind&=~flag;
  if((pt->kind & (port_input|port_output))==0) {
    if(pt->kind&port_file) {

#if SHOW_ERROR_LINE
      /* Cleanup is here so (close-*-port) functions could work too */
      pt->rep.stdio.curr_line = 0;

      if(pt->rep.stdio.filename)
        sc->free(pt->rep.stdio.filename);
#endif

      fclose(pt->rep.stdio.file);
    }
    pt->kind=port_free;
  }
}

/* get new character from input file */
static int inchar(scheme *sc) {
  int c;
  port *pt;

  pt = sc->inport->_object._port;
  if(pt->kind & port_saw_EOF)
    { return EOF; }
  c = basic_inchar(pt);
  if(c == EOF && sc->inport == sc->loadport) {
    /* Instead, set port_saw_EOF */
    pt->kind |= port_saw_EOF;

    /* file_pop(sc); */
    return EOF;
    /* NOTREACHED */
  }
  return c;
}

static int basic_inchar(port *pt) {
  if(pt->kind & port_file) {
    return fgetc(pt->rep.stdio.file);
  } else {
    if(*pt->rep.string.curr == 0 ||
       pt->rep.string.curr == pt->rep.string.past_the_end) {
      return EOF;
    } else {
      return *pt->rep.string.curr++;
    }
  }
}

/* back character to input buffer */
static void backchar(scheme *sc, int c) {
  port *pt;
  if(c==EOF) return;
  pt=sc->inport->_object._port;
  if(pt->kind&port_file) {
    ungetc(c,pt->rep.stdio.file);
  } else {
    if(pt->rep.string.curr!=pt->rep.string.start) {
      --pt->rep.string.curr;
    }
  }
}

static int realloc_port_string(scheme *sc, port *p)
{
  char *start=p->rep.string.start;
  size_t new_size=p->rep.string.past_the_end-start+1+BLOCK_SIZE;
  char *str=sc->malloc(new_size);
  if(str) {
    memset(str,' ',new_size-1);
    str[new_size-1]='\0';
    strcpy(str,start);
    p->rep.string.start=str;
    p->rep.string.past_the_end=str+new_size-1;
    p->rep.string.curr-=start-str;
    sc->free(start);
    return 1;
  } else {
    return 0;
  }
}

INTERFACE void putstr(scheme *sc, const char *s) {
  port *pt=sc->outport->_object._port;
  if(pt->kind&port_file) {
    fputs(s,pt->rep.stdio.file);
    if( pt->rep.stdio.interactive )
         fflush( pt->rep.stdio.file );
  } else {
    for(;*s;s++) {
      if(pt->rep.string.curr!=pt->rep.string.past_the_end) {
        *pt->rep.string.curr++=*s;
      } else if(pt->kind&port_srfi6&&realloc_port_string(sc,pt)) {
        *pt->rep.string.curr++=*s;
      }
    }
  }
}

static void putchars(scheme *sc, const char *s, int len) {
  port *pt=sc->outport->_object._port;
  if(pt->kind&port_file) {
    fwrite(s,1,len,pt->rep.stdio.file);
  } else {
    for(;len;len--) {
      if(pt->rep.string.curr!=pt->rep.string.past_the_end) {
        *pt->rep.string.curr++=*s++;
      } else if(pt->kind&port_srfi6&&realloc_port_string(sc,pt)) {
        *pt->rep.string.curr++=*s++;
      }
    }
  }
}

INTERFACE void putcharacter(scheme *sc, int c) {
  port *pt=sc->outport->_object._port;
  if(pt->kind&port_file) {
    fputc(c,pt->rep.stdio.file);
  } else {
    if(pt->rep.string.curr!=pt->rep.string.past_the_end) {
      *pt->rep.string.curr++=c;
    } else if(pt->kind&port_srfi6&&realloc_port_string(sc,pt)) {
        *pt->rep.string.curr++=c;
    }
  }
}

/* read characters up to delimiter, but cater to character constants */
static char *readstr_upto(scheme *sc, char *delim) {
  char *p = sc->strbuff;

  while ((p - sc->strbuff < sizeof(sc->strbuff)) &&
         !is_one_of(delim, (*p++ = inchar(sc))));

  if(p == sc->strbuff+2 && p[-2] == '\\') {
    *p=0;
  } else {
    backchar(sc,p[-1]);
    *--p = '\0';
  }
  return sc->strbuff;
}

/* read string expression "xxx...xxx" */
static pointer readstrexp(scheme *sc) {
  char *p = sc->strbuff;
  int c;
  int c1=0;
  enum { st_ok, st_bsl, st_x1, st_x2, st_oct1, st_oct2 } state=st_ok;

  for (;;) {
    c=inchar(sc);
    if(c == EOF || p-sc->strbuff > sizeof(sc->strbuff)-1) {
      return sc->F;
    }
    switch(state) {
        case st_ok:
            switch(c) {
                case '\\':
                    state=st_bsl;
                    break;
                case '"':
                    *p=0;
                    return mk_counted_string(sc,sc->strbuff,p-sc->strbuff);
                default:
                    *p++=c;
                    break;
            }
            break;
        case st_bsl:
            switch(c) {
                case '0':
                case '1':
                case '2':
                case '3':
                case '4':
                case '5':
                case '6':
                case '7':
                        state=st_oct1;
                        c1=c-'0';
                        break;
                case 'x':
                case 'X':
                    state=st_x1;
                    c1=0;
                    break;
                case 'n':
                    *p++='\n';
                    state=st_ok;
                    break;
                case 't':
                    *p++='\t';
                    state=st_ok;
                    break;
                case 'r':
                    *p++='\r';
                    state=st_ok;
                    break;
                case '"':
                    *p++='"';
                    state=st_ok;
                    break;
                default:
                    *p++=c;
                    state=st_ok;
                    break;
            }
            break;
        case st_x1:
        case st_x2:
            c=toupper(c);
            if(c>='0' && c<='F') {
                if(c<='9') {
                    c1=(c1<<4)+c-'0';
                } else {
                    c1=(c1<<4)+c-'A'+10;
                }
                if(state==st_x1) {
                    state=st_x2;
                } else {
                    *p++=c1;
                    state=st_ok;
                }
            } else {
                return sc->F;
            }
            break;
        case st_oct1:
        case st_oct2:
            if (c < '0' || c > '7')
            {
                   *p++=c1;
                   backchar(sc, c);
                   state=st_ok;
            }
            else
            {
                if (state==st_oct2 && c1 >= 32)
                    return sc->F;

                   c1=(c1<<3)+(c-'0');

                if (state == st_oct1)
                        state=st_oct2;
                else
                {
                        *p++=c1;
                        state=st_ok;
                   }
            }
            break;

    }
  }
}

/* check c is in chars */
static INLINE int is_one_of(char *s, int c) {
     if(c==EOF) return 1;
     while (*s)
          if (*s++ == c)
               return (1);
     return (0);
}

/* skip white characters */
static INLINE int skipspace(scheme *sc) {
     int c = 0, curr_line = 0;

     do {
         c=inchar(sc);
#if SHOW_ERROR_LINE
         if(c=='\n')
           curr_line++;
#endif
     } while (isspace(c));

/* record it */
#if SHOW_ERROR_LINE
     if (sc->load_stack[sc->file_i].kind & port_file)
       sc->load_stack[sc->file_i].rep.stdio.curr_line += curr_line;
#endif

     if(c!=EOF) {
          backchar(sc,c);
      return 1;
     }
     else
       { return EOF; }
}

/* get token */
static int token(scheme *sc) {
     int c;
     c = skipspace(sc);
     if(c == EOF) { return (TOK_EOF); }
     switch (c=inchar(sc)) {
     case EOF:
          return (TOK_EOF);
     case '(':
          return (TOK_LPAREN);
     case ')':
          return (TOK_RPAREN);
     case '.':
          c=inchar(sc);
          if(is_one_of(" \n\t",c)) {
               return (TOK_DOT);
          } else {
               backchar(sc,c);
               backchar(sc,'.');
               return TOK_ATOM;
          }
     case '\'':
          return (TOK_QUOTE);
     case ';':
           while ((c=inchar(sc)) != '\n' && c!=EOF)
             ;

#if SHOW_ERROR_LINE
           if(c == '\n' && sc->load_stack[sc->file_i].kind & port_file)
             sc->load_stack[sc->file_i].rep.stdio.curr_line++;
#endif

       if(c == EOF)
         { return (TOK_EOF); }
       else
         { return (token(sc));}
     case '"':
          return (TOK_DQUOTE);
     case BACKQUOTE:
          return (TOK_BQUOTE);
     case ',':
         if ((c=inchar(sc)) == '@') {
               return (TOK_ATMARK);
         } else {
               backchar(sc,c);
               return (TOK_COMMA);
         }
     case '#':
          c=inchar(sc);
          if (c == '(') {
               return (TOK_VEC);
          } else if(c == '!') {
               while ((c=inchar(sc)) != '\n' && c!=EOF)
                   ;

#if SHOW_ERROR_LINE
           if(c == '\n' && sc->load_stack[sc->file_i].kind & port_file)
             sc->load_stack[sc->file_i].rep.stdio.curr_line++;
#endif

           if(c == EOF)
             { return (TOK_EOF); }
           else
             { return (token(sc));}
          } else {
               backchar(sc,c);
               if(is_one_of(" tfodxb\\",c)) {
                    return TOK_SHARP_CONST;
               } else {
                    return (TOK_SHARP);
               }
          }
     default:
          backchar(sc,c);
          return (TOK_ATOM);
     }
}

/* ========== Routines for Printing ========== */
#define   ok_abbrev(x)   (is_pair(x) && cdr(x) == sc->NIL)

static void printslashstring(scheme *sc, char *p, int len) {
  int i;
  unsigned char *s=(unsigned char*)p;
  putcharacter(sc,'"');
  for ( i=0; i<len; i++) {
    if(*s==0xff || *s=='"' || *s<' ' || *s=='\\') {
      putcharacter(sc,'\\');
      switch(*s) {
      case '"':
        putcharacter(sc,'"');
        break;
      case '\n':
        putcharacter(sc,'n');
        break;
      case '\t':
        putcharacter(sc,'t');
        break;
      case '\r':
        putcharacter(sc,'r');
        break;
      case '\\':
        putcharacter(sc,'\\');
        break;
      default: {
          int d=*s/16;
          putcharacter(sc,'x');
          if(d<10) {
            putcharacter(sc,d+'0');
          } else {
            putcharacter(sc,d-10+'A');
          }
          d=*s%16;
          if(d<10) {
            putcharacter(sc,d+'0');
          } else {
            putcharacter(sc,d-10+'A');
          }
        }
      }
    } else {
      putcharacter(sc,*s);
    }
    s++;
  }
  putcharacter(sc,'"');
}


/* print atoms */
static void printatom(scheme *sc, pointer l, int f) {
  char *p;
  int len;
  atom2str(sc,l,f,&p,&len);
  putchars(sc,p,len);
}


/* Uses internal buffer unless string pointer is already available */
static void atom2str(scheme *sc, pointer l, int f, char **pp, int *plen) {
     char *p;

     if (l == sc->NIL) {
          p = "()";
     } else if (l == sc->T) {
          p = "#t";
     } else if (l == sc->F) {
          p = "#f";
     } else if (l == sc->EOF_OBJ) {
          p = "#<EOF>";
     } else if (is_port(l)) {
          p = sc->strbuff;
          snprintf(p, STRBUFFSIZE, "#<PORT>");
     } else if (is_number(l)) {
          p = sc->strbuff;
          if (f <= 1 || f == 10) /* f is the base for numbers if > 1 */ {
              if(num_is_integer(l)) {
                   snprintf(p, STRBUFFSIZE, "%ld", ivalue_unchecked(l));
              } else {
                   snprintf(p, STRBUFFSIZE, "%.10g", rvalue_unchecked(l));
                   /* r5rs says there must be a '.' (unless 'e'?) */
                   f = strcspn(p, ".e");
                   if (p[f] == 0) {
                        p[f] = '.'; /* not found, so add '.0' at the end */
                        p[f+1] = '0';
                        p[f+2] = 0;
                   }
              }
          } else {
              long v = ivalue(l);
              if (f == 16) {
                  if (v >= 0)
                    snprintf(p, STRBUFFSIZE, "%lx", v);
                  else
                    snprintf(p, STRBUFFSIZE, "-%lx", -v);
              } else if (f == 8) {
                  if (v >= 0)
                    snprintf(p, STRBUFFSIZE, "%lo", v);
                  else
                    snprintf(p, STRBUFFSIZE, "-%lo", -v);
              } else if (f == 2) {
                  unsigned long b = (v < 0) ? -v : v;
                  p = &p[STRBUFFSIZE-1];
                  *p = 0;
                  do { *--p = (b&1) ? '1' : '0'; b >>= 1; } while (b != 0);
                  if (v < 0) *--p = '-';
              }
          }
     } else if (is_string(l)) {
          if (!f) {
               p = strvalue(l);
          } else { /* Hack, uses the fact that printing is needed */
               *pp=sc->strbuff;
               *plen=0;
               printslashstring(sc, strvalue(l), strlength(l));
               return;
          }
     } else if (is_character(l)) {
          int c=charvalue(l);
          p = sc->strbuff;
          if (!f) {
               p[0]=c;
               p[1]=0;
          } else {
               switch(c) {
               case ' ':
                    snprintf(p,STRBUFFSIZE,"#\\space"); break;
               case '\n':
                    snprintf(p,STRBUFFSIZE,"#\\newline"); break;
               case '\r':
                    snprintf(p,STRBUFFSIZE,"#\\return"); break;
               case '\t':
                    snprintf(p,STRBUFFSIZE,"#\\tab"); break;
               default:
#if USE_ASCII_NAMES
                    if(c==127) {
                         snprintf(p,STRBUFFSIZE, "#\\del");
                         break;
                    } else if(c<32) {
                         snprintf(p, STRBUFFSIZE, "#\\%s", charnames[c]);
                         break;
                    }
#else
                    if(c<32) {
                      snprintf(p,STRBUFFSIZE,"#\\x%x",c); break;
                      break;
                    }
#endif
                    snprintf(p,STRBUFFSIZE,"#\\%c",c); break;
                    break;
               }
          }
     } else if (is_symbol(l)) {
          p = symname(l);
     } else if (is_proc(l)) {
          p = sc->strbuff;
          snprintf(p,STRBUFFSIZE,"#<%s PROCEDURE %ld>", procname(l),procnum(l));
     } else if (is_macro(l)) {
          p = "#<MACRO>";
     } else if (is_closure(l)) {
          p = "#<CLOSURE>";
     } else if (is_promise(l)) {
          p = "#<PROMISE>";
     } else if (is_foreign(l)) {
          p = sc->strbuff;
          snprintf(p,STRBUFFSIZE,"#<FOREIGN PROCEDURE %ld>", procnum(l));
     } else if (is_continuation(l)) {
          p = "#<CONTINUATION>";
     } else {
          p = "#<ERROR>";
     }
     *pp=p;
     *plen=strlen(p);
}
/* ========== Routines for Evaluation Cycle ========== */

/* make closure. c is code. e is environment */
static pointer mk_closure(scheme *sc, pointer c, pointer e) {
     pointer x = get_cell(sc, c, e);

     typeflag(x) = T_CLOSURE;
     car(x) = c;
     cdr(x) = e;
     return (x);
}

/* make continuation. */
static pointer mk_continuation(scheme *sc, pointer d) {
     pointer x = get_cell(sc, sc->NIL, d);

     typeflag(x) = T_CONTINUATION;
     cont_dump(x) = d;
     return (x);
}

static pointer list_star(scheme *sc, pointer d) {
  pointer p, q;
  if(cdr(d)==sc->NIL) {
    return car(d);
  }
  p=cons(sc,car(d),cdr(d));
  q=p;
  while(cdr(cdr(p))!=sc->NIL) {
    d=cons(sc,car(p),cdr(p));
    if(cdr(cdr(p))!=sc->NIL) {
      p=cdr(d);
    }
  }
  cdr(p)=car(cdr(p));
  return q;
}

/* reverse list -- produce new list */
static pointer reverse(scheme *sc, pointer a) {
/* a must be checked by gc */
     pointer p = sc->NIL;

     for ( ; is_pair(a); a = cdr(a)) {
          p = cons(sc, car(a), p);
     }
     return (p);
}

/* reverse list --- in-place */
static pointer reverse_in_place(scheme *sc, pointer term, pointer list) {
     pointer p = list, result = term, q;

     while (p != sc->NIL) {
          q = cdr(p);
          cdr(p) = result;
          result = p;
          p = q;
     }
     return (result);
}

/* append list -- produce new list (in reverse order) */
static pointer revappend(scheme *sc, pointer a, pointer b) {
    pointer result = a;
    pointer p = b;

    while (is_pair(p)) {
        result = cons(sc, car(p), result);
        p = cdr(p);
    }

    if (p == sc->NIL) {
        return result;
    }

    return sc->F;   /* signal an error */
}

/* equivalence of atoms */
int eqv(pointer a, pointer b) {
     if (is_string(a)) {
          if (is_string(b))
               return (strvalue(a) == strvalue(b));
          else
               return (0);
     } else if (is_number(a)) {
          if (is_number(b)) {
               if (num_is_integer(a) == num_is_integer(b))
                    return num_eq(nvalue(a),nvalue(b));
          }
          return (0);
     } else if (is_character(a)) {
          if (is_character(b))
               return charvalue(a)==charvalue(b);
          else
               return (0);
     } else if (is_port(a)) {
          if (is_port(b))
               return a==b;
          else
               return (0);
     } else if (is_proc(a)) {
          if (is_proc(b))
               return procnum(a)==procnum(b);
          else
               return (0);
     } else {
          return (a == b);
     }
}

/* true or false value macro */
/* () is #t in R5RS */
#define is_true(p)       ((p) != sc->F)
#define is_false(p)      ((p) == sc->F)

/* ========== Environment implementation  ========== */

#if !defined(USE_ALIST_ENV) || !defined(USE_OBJECT_LIST)

static int hash_fn(const char *key, int table_size)
{
  unsigned int hashed = 0;
  const char *c;
  int bits_per_int = sizeof(unsigned int)*8;

  for (c = key; *c; c++) {
    /* letters have about 5 bits in them */
    hashed = (hashed<<5) | (hashed>>(bits_per_int-5));
    hashed ^= *c;
  }
  return hashed % table_size;
}
#endif

#ifndef USE_ALIST_ENV

/*
 * In this implementation, each frame of the environment may be
 * a hash table: a vector of alists hashed by variable name.
 * In practice, we use a vector only for the initial frame;
 * subsequent frames are too small and transient for the lookup
 * speed to out-weigh the cost of making a new vector.
 */

static void new_frame_in_env(scheme *sc, pointer old_env)
{
  pointer new_frame;

  /* The interaction-environment has about 300 variables in it. */
  if (old_env == sc->NIL) {
    new_frame = mk_vector(sc, 461);
  } else {
    new_frame = sc->NIL;
  }

  sc->envir = immutable_cons(sc, new_frame, old_env);
  setenvironment(sc->envir);
}

static INLINE void new_slot_spec_in_env(scheme *sc, pointer env,
                                        pointer variable, pointer value)
{
  pointer slot = immutable_cons(sc, variable, value);

  if (is_vector(car(env))) {
    int location = hash_fn(symname(variable), ivalue_unchecked(car(env)));

    set_vector_elem(car(env), location,
                    immutable_cons(sc, slot, vector_elem(car(env), location)));
  } else {
    car(env) = immutable_cons(sc, slot, car(env));
  }
}

static pointer find_slot_in_env(scheme *sc, pointer env, pointer hdl, int all)
{
  pointer x,y;
  int location;

  for (x = env; x != sc->NIL; x = cdr(x)) {
    if (is_vector(car(x))) {
      location = hash_fn(symname(hdl), ivalue_unchecked(car(x)));
      y = vector_elem(car(x), location);
    } else {
      y = car(x);
    }
    for ( ; y != sc->NIL; y = cdr(y)) {
              if (caar(y) == hdl) {
                   break;
              }
         }
         if (y != sc->NIL) {
              break;
         }
         if(!all) {
           return sc->NIL;
         }
    }
    if (x != sc->NIL) {
          return car(y);
    }
    return sc->NIL;
}

#else /* USE_ALIST_ENV */

static INLINE void new_frame_in_env(scheme *sc, pointer old_env)
{
  sc->envir = immutable_cons(sc, sc->NIL, old_env);
  setenvironment(sc->envir);
}

static INLINE void new_slot_spec_in_env(scheme *sc, pointer env,
                                        pointer variable, pointer value)
{
  car(env) = immutable_cons(sc, immutable_cons(sc, variable, value), car(env));
}

static pointer find_slot_in_env(scheme *sc, pointer env, pointer hdl, int all)
{
    pointer x,y;
    for (x = env; x != sc->NIL; x = cdr(x)) {
         for (y = car(x); y != sc->NIL; y = cdr(y)) {
              if (caar(y) == hdl) {
                   break;
              }
         }
         if (y != sc->NIL) {
              break;
         }
         if(!all) {
           return sc->NIL;
         }
    }
    if (x != sc->NIL) {
          return car(y);
    }
    return sc->NIL;
}

#endif /* USE_ALIST_ENV else */

static INLINE void new_slot_in_env(scheme *sc, pointer variable, pointer value)
{
  new_slot_spec_in_env(sc, sc->envir, variable, value);
}

static INLINE void set_slot_in_env(scheme *sc, pointer slot, pointer value)
{
  cdr(slot) = value;
}

static INLINE pointer slot_value_in_env(pointer slot)
{
  return cdr(slot);
}

/* ========== Evaluation Cycle ========== */


static pointer _Error_1(scheme *sc, const char *s, pointer a) {
     const char *str = s;
#if USE_ERROR_HOOK
     pointer x;
     pointer hdl=sc->ERROR_HOOK;
#endif

#if SHOW_ERROR_LINE
     char sbuf[STRBUFFSIZE];

     /* make sure error is not in REPL */
     if (sc->load_stack[sc->file_i].kind & port_file &&
         sc->load_stack[sc->file_i].rep.stdio.file != stdin) {
       int ln = sc->load_stack[sc->file_i].rep.stdio.curr_line;
       const char *fname = sc->load_stack[sc->file_i].rep.stdio.filename;

       /* should never happen */
       if(!fname) fname = "<unknown>";

       /* we started from 0 */
       ln++;
       snprintf(sbuf, STRBUFFSIZE, "(%s : %i) %s", fname, ln, s);

       str = (const char*)sbuf;
     }
#endif

#if USE_ERROR_HOOK
     x=find_slot_in_env(sc,sc->envir,hdl,1);
    if (x != sc->NIL) {
         if(a!=0) {
               sc->code = cons(sc, cons(sc, sc->QUOTE, cons(sc,(a), sc->NIL)), sc->NIL);
         } else {
               sc->code = sc->NIL;
         }
         sc->code = cons(sc, mk_string(sc, str), sc->code);
         setimmutable(car(sc->code));
         sc->code = cons(sc, slot_value_in_env(x), sc->code);
         sc->op = (int)OP_EVAL;
         return sc->T;
    }
#endif

    if(a!=0) {
          sc->args = cons(sc, (a), sc->NIL);
    } else {
          sc->args = sc->NIL;
    }
    sc->args = cons(sc, mk_string(sc, str), sc->args);
    setimmutable(car(sc->args));
    sc->op = (int)OP_ERR0;
    return sc->T;
}
#define Error_1(sc,s, a) return _Error_1(sc,s,a)
#define Error_0(sc,s)    return _Error_1(sc,s,0)

/* Too small to turn into function */
# define  BEGIN     do {
# define  END  } while (0)
#define s_goto(sc,a) BEGIN                                  \
    sc->op = (int)(a);                                      \
    return sc->T; END

#define s_return(sc,a) return _s_return(sc,a)

#ifndef USE_SCHEME_STACK

/* this structure holds all the interpreter's registers */
struct dump_stack_frame {
  enum scheme_opcodes op;
  pointer args;
  pointer envir;
  pointer code;
};

#define STACK_GROWTH 3

static void s_save(scheme *sc, enum scheme_opcodes op, pointer args, pointer code)
{
  int nframes = (int)sc->dump;
  struct dump_stack_frame *next_frame;

  /* enough room for the next frame? */
  if (nframes >= sc->dump_size) {
    sc->dump_size += STACK_GROWTH;
    /* alas there is no sc->realloc */
    sc->dump_base = realloc(sc->dump_base,
                            sizeof(struct dump_stack_frame) * sc->dump_size);
  }
  next_frame = (struct dump_stack_frame *)sc->dump_base + nframes;
  next_frame->op = op;
  next_frame->args = args;
  next_frame->envir = sc->envir;
  next_frame->code = code;
  sc->dump = (pointer)(nframes+1);
}

static pointer _s_return(scheme *sc, pointer a)
{
  int nframes = (int)sc->dump;
  struct dump_stack_frame *frame;

  sc->value = (a);
  if (nframes <= 0) {
    return sc->NIL;
  }
  nframes--;
  frame = (struct dump_stack_frame *)sc->dump_base + nframes;
  sc->op = frame->op;
  sc->args = frame->args;
  sc->envir = frame->envir;
  sc->code = frame->code;
  sc->dump = (pointer)nframes;
  return sc->T;
}

static INLINE void dump_stack_reset(scheme *sc)
{
  /* in this implementation, sc->dump is the number of frames on the stack */
  sc->dump = (pointer)0;
}

static INLINE void dump_stack_initialize(scheme *sc)
{
  sc->dump_size = 0;
  sc->dump_base = NULL;
  dump_stack_reset(sc);
}

static void dump_stack_free(scheme *sc)
{
  free(sc->dump_base);
  sc->dump_base = NULL;
  sc->dump = (pointer)0;
  sc->dump_size = 0;
}

static INLINE void dump_stack_mark(scheme *sc)
{
  int nframes = (int)sc->dump;
  int i;
  for(i=0; i<nframes; i++) {
    struct dump_stack_frame *frame;
    frame = (struct dump_stack_frame *)sc->dump_base + i;
    mark(frame->args);
    mark(frame->envir);
    mark(frame->code);
  }
}

#else

static INLINE void dump_stack_reset(scheme *sc)
{
  sc->dump = sc->NIL;
}

static INLINE void dump_stack_initialize(scheme *sc)
{
  dump_stack_reset(sc);
}

static void dump_stack_free(scheme *sc)
{
  sc->dump = sc->NIL;
}

static pointer _s_return(scheme *sc, pointer a) {
    sc->value = (a);
    if(sc->dump==sc->NIL) return sc->NIL;
    sc->op = ivalue(car(sc->dump));
    sc->args = cadr(sc->dump);
    sc->envir = caddr(sc->dump);
    sc->code = cadddr(sc->dump);
    sc->dump = cddddr(sc->dump);
    return sc->T;
}

static void s_save(scheme *sc, enum scheme_opcodes op, pointer args, pointer code) {
    sc->dump = cons(sc, sc->envir, cons(sc, (code), sc->dump));
    sc->dump = cons(sc, (args), sc->dump);
    sc->dump = cons(sc, mk_integer(sc, (long)(op)), sc->dump);
}

static INLINE void dump_stack_mark(scheme *sc)
{
  mark(sc->dump);
}
#endif

#define s_retbool(tf)    s_return(sc,(tf) ? sc->T : sc->F)

static pointer opexe_0(scheme *sc, enum scheme_opcodes op) {
     pointer x, y;

     switch (op) {
     case OP_LOAD:       /* load */
          if(file_interactive(sc)) {
               fprintf(sc->outport->_object._port->rep.stdio.file,
               "Loading %s\n", strvalue(car(sc->args)));
          }
          if (!file_push(sc,strvalue(car(sc->args)))) {
               Error_1(sc,"unable to open", car(sc->args));
          }
      else
        {
          sc->args = mk_integer(sc,sc->file_i);
          s_goto(sc,OP_T0LVL);
        }

     case OP_T0LVL: /* top level */
       /* If we reached the end of file, this loop is done. */
       if(sc->loadport->_object._port->kind & port_saw_EOF)
     {
       if(sc->file_i == 0)
         {
           sc->args=sc->NIL;
           s_goto(sc,OP_QUIT);
         }
       else
         {
           file_pop(sc);
           s_return(sc,sc->value);
         }
       /* NOTREACHED */
     }

       /* If interactive, be nice to user. */
       if(file_interactive(sc))
     {
       sc->envir = sc->global_env;
       dump_stack_reset(sc);
       putstr(sc,"\n");
       putstr(sc,prompt);
     }

       /* Set up another iteration of REPL */
       sc->nesting=0;
       sc->save_inport=sc->inport;
       sc->inport = sc->loadport;
       s_save(sc,OP_T0LVL, sc->NIL, sc->NIL);
       s_save(sc,OP_VALUEPRINT, sc->NIL, sc->NIL);
       s_save(sc,OP_T1LVL, sc->NIL, sc->NIL);
       s_goto(sc,OP_READ_INTERNAL);

     case OP_T1LVL: /* top level */
          sc->code = sc->value;
          sc->inport=sc->save_inport;
          s_goto(sc,OP_EVAL);

     case OP_READ_INTERNAL:       /* internal read */
          sc->tok = token(sc);
          if(sc->tok==TOK_EOF)
        { s_return(sc,sc->EOF_OBJ); }
          s_goto(sc,OP_RDSEXPR);

     case OP_GENSYM:
          s_return(sc, gensym(sc));

     case OP_VALUEPRINT: /* print evaluation result */
          /* OP_VALUEPRINT is always pushed, because when changing from
             non-interactive to interactive mode, it needs to be
             already on the stack */
       if(sc->tracing) {
         putstr(sc,"\nGives: ");
       }
       if(file_interactive(sc)) {
         sc->print_flag = 1;
         sc->args = sc->value;
         s_goto(sc,OP_P0LIST);
       } else {
         s_return(sc,sc->value);
       }

     case OP_EVAL:       /* main part of evaluation */
#if USE_TRACING
       if(sc->tracing) {
         /*s_save(sc,OP_VALUEPRINT,sc->NIL,sc->NIL);*/
         s_save(sc,OP_REAL_EVAL,sc->args,sc->code);
         sc->args=sc->code;
         putstr(sc,"\nEval: ");
         s_goto(sc,OP_P0LIST);
       }
       /* fall through */
     case OP_REAL_EVAL:
#endif
          if (is_symbol(sc->code)) {    /* symbol */
               x=find_slot_in_env(sc,sc->envir,sc->code,1);
               if (x != sc->NIL) {
                    s_return(sc,slot_value_in_env(x));
               } else {
                    Error_1(sc,"eval: unbound variable:", sc->code);
               }
          } else if (is_pair(sc->code)) {
               if (is_syntax(x = car(sc->code))) {     /* SYNTAX */
                    sc->code = cdr(sc->code);
                    s_goto(sc,syntaxnum(x));
               } else {/* first, eval top element and eval arguments */
                    s_save(sc,OP_E0ARGS, sc->NIL, sc->code);
                    /* If no macros => s_save(sc,OP_E1ARGS, sc->NIL, cdr(sc->code));*/
                    sc->code = car(sc->code);
                    s_goto(sc,OP_EVAL);
               }
          } else {
               s_return(sc,sc->code);
          }

     case OP_E0ARGS:     /* eval arguments */
          if (is_macro(sc->value)) {    /* macro expansion */
               s_save(sc,OP_DOMACRO, sc->NIL, sc->NIL);
               sc->args = cons(sc,sc->code, sc->NIL);
               sc->code = sc->value;
               s_goto(sc,OP_APPLY);
          } else {
               sc->code = cdr(sc->code);
               s_goto(sc,OP_E1ARGS);
          }

     case OP_E1ARGS:     /* eval arguments */
          sc->args = cons(sc, sc->value, sc->args);
          if (is_pair(sc->code)) { /* continue */
               s_save(sc,OP_E1ARGS, sc->args, cdr(sc->code));
               sc->code = car(sc->code);
               sc->args = sc->NIL;
               s_goto(sc,OP_EVAL);
          } else {  /* end */
               sc->args = reverse_in_place(sc, sc->NIL, sc->args);
               sc->code = car(sc->args);
               sc->args = cdr(sc->args);
               s_goto(sc,OP_APPLY);
          }

#if USE_TRACING
     case OP_TRACING: {
       int tr=sc->tracing;
       sc->tracing=ivalue(car(sc->args));
       s_return(sc,mk_integer(sc,tr));
     }
#endif

     case OP_APPLY:      /* apply 'code' to 'args' */
#if USE_TRACING
       if(sc->tracing) {
         s_save(sc,OP_REAL_APPLY,sc->args,sc->code);
         sc->print_flag = 1;
         /*  sc->args=cons(sc,sc->code,sc->args);*/
         putstr(sc,"\nApply to: ");
         s_goto(sc,OP_P0LIST);
       }
       /* fall through */
     case OP_REAL_APPLY:
#endif
          if (is_proc(sc->code)) {
               s_goto(sc,procnum(sc->code));   /* PROCEDURE */
          } else if (is_foreign(sc->code))
            {
              /* Keep nested calls from GC'ing the arglist */
              push_recent_alloc(sc,sc->args,sc->NIL);
               x=sc->code->_object._ff(sc,sc->args);
               s_return(sc,x);
          } else if (is_closure(sc->code) || is_macro(sc->code)
             || is_promise(sc->code)) { /* CLOSURE */
        /* Should not accept promise */
               /* make environment */
               new_frame_in_env(sc, closure_env(sc->code));
               for (x = car(closure_code(sc->code)), y = sc->args;
                    is_pair(x); x = cdr(x), y = cdr(y)) {
                    if (y == sc->NIL) {
                         Error_0(sc,"not enough arguments");
                    } else {
                         new_slot_in_env(sc, car(x), car(y));
                    }
               }
               if (x == sc->NIL) {
                    /*--
                     * if (y != sc->NIL) {
                     *   Error_0(sc,"too many arguments");
                     * }
                     */
               } else if (is_symbol(x))
                    new_slot_in_env(sc, x, y);
               else {
                    Error_1(sc,"syntax error in closure: not a symbol:", x);
               }
               sc->code = cdr(closure_code(sc->code));
               sc->args = sc->NIL;
               s_goto(sc,OP_BEGIN);
          } else if (is_continuation(sc->code)) { /* CONTINUATION */
               sc->dump = cont_dump(sc->code);
               s_return(sc,sc->args != sc->NIL ? car(sc->args) : sc->NIL);
          } else {
               Error_0(sc,"illegal function");
          }

     case OP_DOMACRO:    /* do macro */
          sc->code = sc->value;
          s_goto(sc,OP_EVAL);

#if 1
     case OP_LAMBDA:     /* lambda */
          /* If the hook is defined, apply it to sc->code, otherwise
             set sc->value fall thru */
          {
               pointer f=find_slot_in_env(sc,sc->envir,sc->COMPILE_HOOK,1);
               if(f==sc->NIL) {
                    sc->value = sc->code;
                    /* Fallthru */
               } else {
                    s_save(sc,OP_LAMBDA1,sc->args,sc->code);
                    sc->args=cons(sc,sc->code,sc->NIL);
                    sc->code=slot_value_in_env(f);
                    s_goto(sc,OP_APPLY);
               }
          }

     case OP_LAMBDA1:
          s_return(sc,mk_closure(sc, sc->value, sc->envir));

#else
     case OP_LAMBDA:     /* lambda */
          s_return(sc,mk_closure(sc, sc->code, sc->envir));

#endif

     case OP_MKCLOSURE: /* make-closure */
       x=car(sc->args);
       if(car(x)==sc->LAMBDA) {
         x=cdr(x);
       }
       if(cdr(sc->args)==sc->NIL) {
         y=sc->envir;
       } else {
         y=cadr(sc->args);
       }
       s_return(sc,mk_closure(sc, x, y));

     case OP_QUOTE:      /* quote */
          s_return(sc,car(sc->code));

     case OP_DEF0:  /* define */
          if(is_immutable(car(sc->code)))
            Error_1(sc,"define: unable to alter immutable", car(sc->code));

          if (is_pair(car(sc->code))) {
               x = caar(sc->code);
               sc->code = cons(sc, sc->LAMBDA, cons(sc, cdar(sc->code), cdr(sc->code)));
          } else {
               x = car(sc->code);
               sc->code = cadr(sc->code);
          }
          if (!is_symbol(x)) {
               Error_0(sc,"variable is not a symbol");
          }
          s_save(sc,OP_DEF1, sc->NIL, x);
          s_goto(sc,OP_EVAL);

     case OP_DEF1:  /* define */
          x=find_slot_in_env(sc,sc->envir,sc->code,0);
          if (x != sc->NIL) {
               set_slot_in_env(sc, x, sc->value);
          } else {
               new_slot_in_env(sc, sc->code, sc->value);
          }
          s_return(sc,sc->code);


     case OP_DEFP:  /* defined? */
          x=sc->envir;
          if(cdr(sc->args)!=sc->NIL) {
               x=cadr(sc->args);
          }
          s_retbool(find_slot_in_env(sc,x,car(sc->args),1)!=sc->NIL);

     case OP_SET0:       /* set! */
          if(is_immutable(car(sc->code)))
                Error_1(sc,"set!: unable to alter immutable variable",car(sc->code));
          s_save(sc,OP_SET1, sc->NIL, car(sc->code));
          sc->code = cadr(sc->code);
          s_goto(sc,OP_EVAL);

     case OP_SET1:       /* set! */
          y=find_slot_in_env(sc,sc->envir,sc->code,1);
          if (y != sc->NIL) {
               set_slot_in_env(sc, y, sc->value);
               s_return(sc,sc->value);
          } else {
               Error_1(sc,"set!: unbound variable:", sc->code);
          }


     case OP_BEGIN:      /* begin */
          if (!is_pair(sc->code)) {
               s_return(sc,sc->code);
          }
          if (cdr(sc->code) != sc->NIL) {
               s_save(sc,OP_BEGIN, sc->NIL, cdr(sc->code));
          }
          sc->code = car(sc->code);
          s_goto(sc,OP_EVAL);

     case OP_IF0:        /* if */
          s_save(sc,OP_IF1, sc->NIL, cdr(sc->code));
          sc->code = car(sc->code);
          s_goto(sc,OP_EVAL);

     case OP_IF1:        /* if */
          if (is_true(sc->value))
               sc->code = car(sc->code);
          else
               sc->code = cadr(sc->code);  /* (if #f 1) ==> () because
                                            * car(sc->NIL) = sc->NIL */
          s_goto(sc,OP_EVAL);

     case OP_LET0:       /* let */
          sc->args = sc->NIL;
          sc->value = sc->code;
          sc->code = is_symbol(car(sc->code)) ? cadr(sc->code) : car(sc->code);
          s_goto(sc,OP_LET1);

     case OP_LET1:       /* let (calculate parameters) */
          sc->args = cons(sc, sc->value, sc->args);
          if (is_pair(sc->code)) { /* continue */
               if (!is_pair(car(sc->code)) || !is_pair(cdar(sc->code))) {
                    Error_1(sc, "Bad syntax of binding spec in let :",
                            car(sc->code));
               }
               s_save(sc,OP_LET1, sc->args, cdr(sc->code));
               sc->code = cadar(sc->code);
               sc->args = sc->NIL;
               s_goto(sc,OP_EVAL);
          } else {  /* end */
               sc->args = reverse_in_place(sc, sc->NIL, sc->args);
               sc->code = car(sc->args);
               sc->args = cdr(sc->args);
               s_goto(sc,OP_LET2);
          }

     case OP_LET2:       /* let */
          new_frame_in_env(sc, sc->envir);
          for (x = is_symbol(car(sc->code)) ? cadr(sc->code) : car(sc->code), y = sc->args;
               y != sc->NIL; x = cdr(x), y = cdr(y)) {
               new_slot_in_env(sc, caar(x), car(y));
          }
          if (is_symbol(car(sc->code))) {    /* named let */
               for (x = cadr(sc->code), sc->args = sc->NIL; x != sc->NIL; x = cdr(x)) {
                    if (!is_pair(x))
                        Error_1(sc, "Bad syntax of binding in let :", x);
                    if (!is_list(sc, car(x)))
                        Error_1(sc, "Bad syntax of binding in let :", car(x));
                    sc->args = cons(sc, caar(x), sc->args);
               }
               x = mk_closure(sc, cons(sc, reverse_in_place(sc, sc->NIL, sc->args), cddr(sc->code)), sc->envir);
               new_slot_in_env(sc, car(sc->code), x);
               sc->code = cddr(sc->code);
               sc->args = sc->NIL;
          } else {
               sc->code = cdr(sc->code);
               sc->args = sc->NIL;
          }
          s_goto(sc,OP_BEGIN);

     case OP_LET0AST:    /* let* */
          if (car(sc->code) == sc->NIL) {
               new_frame_in_env(sc, sc->envir);
               sc->code = cdr(sc->code);
               s_goto(sc,OP_BEGIN);
          }
          if(!is_pair(car(sc->code)) || !is_pair(caar(sc->code)) || !is_pair(cdaar(sc->code))) {
               Error_1(sc,"Bad syntax of binding spec in let* :",car(sc->code));
          }
          s_save(sc,OP_LET1AST, cdr(sc->code), car(sc->code));
          sc->code = cadaar(sc->code);
          s_goto(sc,OP_EVAL);

     case OP_LET1AST:    /* let* (make new frame) */
          new_frame_in_env(sc, sc->envir);
          s_goto(sc,OP_LET2AST);

     case OP_LET2AST:    /* let* (calculate parameters) */
          new_slot_in_env(sc, caar(sc->code), sc->value);
          sc->code = cdr(sc->code);
          if (is_pair(sc->code)) { /* continue */
               s_save(sc,OP_LET2AST, sc->args, sc->code);
               sc->code = cadar(sc->code);
               sc->args = sc->NIL;
               s_goto(sc,OP_EVAL);
          } else {  /* end */
               sc->code = sc->args;
               sc->args = sc->NIL;
               s_goto(sc,OP_BEGIN);
          }
     default:
          snprintf(sc->strbuff,STRBUFFSIZE,"%d: illegal operator", sc->op);
          Error_0(sc,sc->strbuff);
     }
     return sc->T;
}

static pointer opexe_1(scheme *sc, enum scheme_opcodes op) {
     pointer x, y;

     switch (op) {
     case OP_LET0REC:    /* letrec */
          new_frame_in_env(sc, sc->envir);
          sc->args = sc->NIL;
          sc->value = sc->code;
          sc->code = car(sc->code);
          s_goto(sc,OP_LET1REC);

     case OP_LET1REC:    /* letrec (calculate parameters) */
          sc->args = cons(sc, sc->value, sc->args);
          if (is_pair(sc->code)) { /* continue */
               if (!is_pair(car(sc->code)) || !is_pair(cdar(sc->code))) {
                    Error_1(sc, "Bad syntax of binding spec in letrec :",
                            car(sc->code));
               }
               s_save(sc,OP_LET1REC, sc->args, cdr(sc->code));
               sc->code = cadar(sc->code);
               sc->args = sc->NIL;
               s_goto(sc,OP_EVAL);
          } else {  /* end */
               sc->args = reverse_in_place(sc, sc->NIL, sc->args);
               sc->code = car(sc->args);
               sc->args = cdr(sc->args);
               s_goto(sc,OP_LET2REC);
          }

     case OP_LET2REC:    /* letrec */
          for (x = car(sc->code), y = sc->args; y != sc->NIL; x = cdr(x), y = cdr(y)) {
               new_slot_in_env(sc, caar(x), car(y));
          }
          sc->code = cdr(sc->code);
          sc->args = sc->NIL;
          s_goto(sc,OP_BEGIN);

     case OP_COND0:      /* cond */
          if (!is_pair(sc->code)) {
               Error_0(sc,"syntax error in cond");
          }
          s_save(sc,OP_COND1, sc->NIL, sc->code);
          sc->code = caar(sc->code);
          s_goto(sc,OP_EVAL);

     case OP_COND1:      /* cond */
          if (is_true(sc->value)) {
               if ((sc->code = cdar(sc->code)) == sc->NIL) {
                    s_return(sc,sc->value);
               }
               if(car(sc->code)==sc->FEED_TO) {
                    if(!is_pair(cdr(sc->code))) {
                         Error_0(sc,"syntax error in cond");
                    }
                    x=cons(sc, sc->QUOTE, cons(sc, sc->value, sc->NIL));
                    sc->code=cons(sc,cadr(sc->code),cons(sc,x,sc->NIL));
                    s_goto(sc,OP_EVAL);
               }
               s_goto(sc,OP_BEGIN);
          } else {
               if ((sc->code = cdr(sc->code)) == sc->NIL) {
                    s_return(sc,sc->NIL);
               } else {
                    s_save(sc,OP_COND1, sc->NIL, sc->code);
                    sc->code = caar(sc->code);
                    s_goto(sc,OP_EVAL);
               }
          }

     case OP_DELAY:      /* delay */
          x = mk_closure(sc, cons(sc, sc->NIL, sc->code), sc->envir);
          typeflag(x)=T_PROMISE;
          s_return(sc,x);

     case OP_AND0:       /* and */
          if (sc->code == sc->NIL) {
               s_return(sc,sc->T);
          }
          s_save(sc,OP_AND1, sc->NIL, cdr(sc->code));
          sc->code = car(sc->code);
          s_goto(sc,OP_EVAL);

     case OP_AND1:       /* and */
          if (is_false(sc->value)) {
               s_return(sc,sc->value);
          } else if (sc->code == sc->NIL) {
               s_return(sc,sc->value);
          } else {
               s_save(sc,OP_AND1, sc->NIL, cdr(sc->code));
               sc->code = car(sc->code);
               s_goto(sc,OP_EVAL);
          }

     case OP_OR0:        /* or */
          if (sc->code == sc->NIL) {
               s_return(sc,sc->F);
          }
          s_save(sc,OP_OR1, sc->NIL, cdr(sc->code));
          sc->code = car(sc->code);
          s_goto(sc,OP_EVAL);

     case OP_OR1:        /* or */
          if (is_true(sc->value)) {
               s_return(sc,sc->value);
          } else if (sc->code == sc->NIL) {
               s_return(sc,sc->value);
          } else {
               s_save(sc,OP_OR1, sc->NIL, cdr(sc->code));
               sc->code = car(sc->code);
               s_goto(sc,OP_EVAL);
          }

     case OP_C0STREAM:   /* cons-stream */
          s_save(sc,OP_C1STREAM, sc->NIL, cdr(sc->code));
          sc->code = car(sc->code);
          s_goto(sc,OP_EVAL);

     case OP_C1STREAM:   /* cons-stream */
          sc->args = sc->value;  /* save sc->value to register sc->args for gc */
          x = mk_closure(sc, cons(sc, sc->NIL, sc->code), sc->envir);
          typeflag(x)=T_PROMISE;
          s_return(sc,cons(sc, sc->args, x));

     case OP_MACRO0:     /* macro */
          if (is_pair(car(sc->code))) {
               x = caar(sc->code);
               sc->code = cons(sc, sc->LAMBDA, cons(sc, cdar(sc->code), cdr(sc->code)));
          } else {
               x = car(sc->code);
               sc->code = cadr(sc->code);
          }
          if (!is_symbol(x)) {
               Error_0(sc,"variable is not a symbol");
          }
          s_save(sc,OP_MACRO1, sc->NIL, x);
          s_goto(sc,OP_EVAL);

     case OP_MACRO1:     /* macro */
          typeflag(sc->value) = T_MACRO;
          x = find_slot_in_env(sc, sc->envir, sc->code, 0);
          if (x != sc->NIL) {
               set_slot_in_env(sc, x, sc->value);
          } else {
               new_slot_in_env(sc, sc->code, sc->value);
          }
          s_return(sc,sc->code);

     case OP_CASE0:      /* case */
          s_save(sc,OP_CASE1, sc->NIL, cdr(sc->code));
          sc->code = car(sc->code);
          s_goto(sc,OP_EVAL);

     case OP_CASE1:      /* case */
          for (x = sc->code; x != sc->NIL; x = cdr(x)) {
               if (!is_pair(y = caar(x))) {
                    break;
               }
               for ( ; y != sc->NIL; y = cdr(y)) {
                    if (eqv(car(y), sc->value)) {
                         break;
                    }
               }
               if (y != sc->NIL) {
                    break;
               }
          }
          if (x != sc->NIL) {
               if (is_pair(caar(x))) {
                    sc->code = cdar(x);
                    s_goto(sc,OP_BEGIN);
               } else {/* else */
                    s_save(sc,OP_CASE2, sc->NIL, cdar(x));
                    sc->code = caar(x);
                    s_goto(sc,OP_EVAL);
               }
          } else {
               s_return(sc,sc->NIL);
          }

     case OP_CASE2:      /* case */
          if (is_true(sc->value)) {
               s_goto(sc,OP_BEGIN);
          } else {
               s_return(sc,sc->NIL);
          }

     case OP_PAPPLY:     /* apply */
          sc->code = car(sc->args);
          sc->args = list_star(sc,cdr(sc->args));
          /*sc->args = cadr(sc->args);*/
          s_goto(sc,OP_APPLY);

     case OP_PEVAL: /* eval */
          if(cdr(sc->args)!=sc->NIL) {
               sc->envir=cadr(sc->args);
          }
          sc->code = car(sc->args);
          s_goto(sc,OP_EVAL);

     case OP_CONTINUATION:    /* call-with-current-continuation */
          sc->code = car(sc->args);
          sc->args = cons(sc, mk_continuation(sc, sc->dump), sc->NIL);
          s_goto(sc,OP_APPLY);

     default:
          snprintf(sc->strbuff,STRBUFFSIZE,"%d: illegal operator", sc->op);
          Error_0(sc,sc->strbuff);
     }
     return sc->T;
}

static pointer opexe_2(scheme *sc, enum scheme_opcodes op) {
     pointer x;
     num v;
#if USE_MATH
     double dd;
#endif

     switch (op) {
#if USE_MATH
     case OP_INEX2EX:    /* inexact->exact */
          x=car(sc->args);
          if(num_is_integer(x)) {
               s_return(sc,x);
          } else if(modf(rvalue_unchecked(x),&dd)==0.0) {
               s_return(sc,mk_integer(sc,ivalue(x)));
          } else {
               Error_1(sc,"inexact->exact: not integral:",x);
          }

     case OP_EXP:
          x=car(sc->args);
          s_return(sc, mk_real(sc, exp(rvalue(x))));

     case OP_LOG:
          x=car(sc->args);
          s_return(sc, mk_real(sc, log(rvalue(x))));

     case OP_SIN:
          x=car(sc->args);
          s_return(sc, mk_real(sc, sin(rvalue(x))));

     case OP_COS:
          x=car(sc->args);
          s_return(sc, mk_real(sc, cos(rvalue(x))));

     case OP_TAN:
          x=car(sc->args);
          s_return(sc, mk_real(sc, tan(rvalue(x))));

     case OP_ASIN:
          x=car(sc->args);
          s_return(sc, mk_real(sc, asin(rvalue(x))));

     case OP_ACOS:
          x=car(sc->args);
          s_return(sc, mk_real(sc, acos(rvalue(x))));

     case OP_ATAN:
          x=car(sc->args);
          if(cdr(sc->args)==sc->NIL) {
               s_return(sc, mk_real(sc, atan(rvalue(x))));
          } else {
               pointer y=cadr(sc->args);
               s_return(sc, mk_real(sc, atan2(rvalue(x),rvalue(y))));
          }

     case OP_SQRT:
          x=car(sc->args);
          s_return(sc, mk_real(sc, sqrt(rvalue(x))));

     case OP_EXPT: {
          double result;
          int real_result=1;
          pointer y=cadr(sc->args);
          x=car(sc->args);
          if (num_is_integer(x) && num_is_integer(y))
             real_result=0;
          /* This 'if' is an R5RS compatibility fix. */
          /* NOTE: Remove this 'if' fix for R6RS.    */
          if (rvalue(x) == 0 && rvalue(y) < 0) {
             result = 0.0;
          } else {
             result = pow(rvalue(x),rvalue(y));
          }
          /* Before returning integer result make sure we can. */
          /* If the test fails, result is too big for integer. */
          if (!real_result)
          {
            long result_as_long = (long)result;
            if (result != (double)result_as_long)
              real_result = 1;
          }
          if (real_result) {
             s_return(sc, mk_real(sc, result));
          } else {
             s_return(sc, mk_integer(sc, result));
          }
     }

     case OP_FLOOR:
          x=car(sc->args);
          s_return(sc, mk_real(sc, floor(rvalue(x))));

     case OP_CEILING:
          x=car(sc->args);
          s_return(sc, mk_real(sc, ceil(rvalue(x))));

     case OP_TRUNCATE : {
          double rvalue_of_x ;
          x=car(sc->args);
          rvalue_of_x = rvalue(x) ;
          if (rvalue_of_x > 0) {
            s_return(sc, mk_real(sc, floor(rvalue_of_x)));
          } else {
            s_return(sc, mk_real(sc, ceil(rvalue_of_x)));
          }
     }

     case OP_ROUND:
        x=car(sc->args);
        if (num_is_integer(x))
            s_return(sc, x);
        s_return(sc, mk_real(sc, round_per_R5RS(rvalue(x))));
#endif

     case OP_ADD:        /* + */
       v=num_zero;
       for (x = sc->args; x != sc->NIL; x = cdr(x)) {
         v=num_add(v,nvalue(car(x)));
       }
       s_return(sc,mk_number(sc, v));

     case OP_MUL:        /* * */
       v=num_one;
       for (x = sc->args; x != sc->NIL; x = cdr(x)) {
         v=num_mul(v,nvalue(car(x)));
       }
       s_return(sc,mk_number(sc, v));

     case OP_SUB:        /* - */
       if(cdr(sc->args)==sc->NIL) {
         x=sc->args;
         v=num_zero;
       } else {
         x = cdr(sc->args);
         v = nvalue(car(sc->args));
       }
       for (; x != sc->NIL; x = cdr(x)) {
         v=num_sub(v,nvalue(car(x)));
       }
       s_return(sc,mk_number(sc, v));

     case OP_DIV:        /* / */
       if(cdr(sc->args)==sc->NIL) {
         x=sc->args;
         v=num_one;
       } else {
         x = cdr(sc->args);
         v = nvalue(car(sc->args));
       }
       for (; x != sc->NIL; x = cdr(x)) {
         if (!is_zero_double(rvalue(car(x))))
           v=num_div(v,nvalue(car(x)));
         else {
           Error_0(sc,"/: division by zero");
         }
       }
       s_return(sc,mk_number(sc, v));

     case OP_INTDIV:        /* quotient */
          if(cdr(sc->args)==sc->NIL) {
               x=sc->args;
               v=num_one;
          } else {
               x = cdr(sc->args);
               v = nvalue(car(sc->args));
          }
          for (; x != sc->NIL; x = cdr(x)) {
               if (ivalue(car(x)) != 0)
                    v=num_intdiv(v,nvalue(car(x)));
               else {
                    Error_0(sc,"quotient: division by zero");
               }
          }
          s_return(sc,mk_number(sc, v));

     case OP_REM:        /* remainder */
          v = nvalue(car(sc->args));
          if (ivalue(cadr(sc->args)) != 0)
               v=num_rem(v,nvalue(cadr(sc->args)));
          else {
               Error_0(sc,"remainder: division by zero");
          }
          s_return(sc,mk_number(sc, v));

     case OP_MOD:        /* modulo */
          v = nvalue(car(sc->args));
          if (ivalue(cadr(sc->args)) != 0)
               v=num_mod(v,nvalue(cadr(sc->args)));
          else {
               Error_0(sc,"modulo: division by zero");
          }
          s_return(sc,mk_number(sc, v));

     case OP_CAR:        /* car */
          s_return(sc,caar(sc->args));

     case OP_CDR:        /* cdr */
          s_return(sc,cdar(sc->args));

     case OP_CONS:       /* cons */
          cdr(sc->args) = cadr(sc->args);
          s_return(sc,sc->args);

     case OP_SETCAR:     /* set-car! */
       if(!is_immutable(car(sc->args))) {
         caar(sc->args) = cadr(sc->args);
         s_return(sc,car(sc->args));
       } else {
         Error_0(sc,"set-car!: unable to alter immutable pair");
       }

     case OP_SETCDR:     /* set-cdr! */
       if(!is_immutable(car(sc->args))) {
         cdar(sc->args) = cadr(sc->args);
         s_return(sc,car(sc->args));
       } else {
         Error_0(sc,"set-cdr!: unable to alter immutable pair");
       }

     case OP_CHAR2INT: { /* char->integer */
          char c;
          c=(char)ivalue(car(sc->args));
          s_return(sc,mk_integer(sc,(unsigned char)c));
     }

     case OP_INT2CHAR: { /* integer->char */
          unsigned char c;
          c=(unsigned char)ivalue(car(sc->args));
          s_return(sc,mk_character(sc,(char)c));
     }

     case OP_CHARUPCASE: {
          unsigned char c;
          c=(unsigned char)ivalue(car(sc->args));
          c=toupper(c);
          s_return(sc,mk_character(sc,(char)c));
     }

     case OP_CHARDNCASE: {
          unsigned char c;
          c=(unsigned char)ivalue(car(sc->args));
          c=tolower(c);
          s_return(sc,mk_character(sc,(char)c));
     }

     case OP_STR2SYM:  /* string->symbol */
          s_return(sc,mk_symbol(sc,strvalue(car(sc->args))));

     case OP_STR2ATOM: /* string->atom */ {
          char *s=strvalue(car(sc->args));
          long pf = 0;
          if(cdr(sc->args)!=sc->NIL) {
            /* we know cadr(sc->args) is a natural number */
            /* see if it is 2, 8, 10, or 16, or error */
            pf = ivalue_unchecked(cadr(sc->args));
            if(pf == 16 || pf == 10 || pf == 8 || pf == 2) {
               /* base is OK */
            }
            else {
              pf = -1;
            }
          }
          if (pf < 0) {
            Error_1(sc, "string->atom: bad base:", cadr(sc->args));
          } else if(*s=='#') /* no use of base! */ {
            s_return(sc, mk_sharp_const(sc, s+1));
          } else {
            if (pf == 0 || pf == 10) {
              s_return(sc, mk_atom(sc, s));
            }
            else {
              char *ep;
              long iv = strtol(s,&ep,(int )pf);
              if (*ep == 0) {
                s_return(sc, mk_integer(sc, iv));
              }
              else {
                s_return(sc, sc->F);
              }
            }
          }
        }

     case OP_SYM2STR: /* symbol->string */
          x=mk_string(sc,symname(car(sc->args)));
          setimmutable(x);
          s_return(sc,x);

     case OP_ATOM2STR: /* atom->string */ {
          long pf = 0;
          x=car(sc->args);
          if(cdr(sc->args)!=sc->NIL) {
            /* we know cadr(sc->args) is a natural number */
            /* see if it is 2, 8, 10, or 16, or error */
            pf = ivalue_unchecked(cadr(sc->args));
            if(is_number(x) && (pf == 16 || pf == 10 || pf == 8 || pf == 2)) {
              /* base is OK */
            }
            else {
              pf = -1;
            }
          }
          if (pf < 0) {
            Error_1(sc, "atom->string: bad base:", cadr(sc->args));
          } else if(is_number(x) || is_character(x) || is_string(x) || is_symbol(x)) {
            char *p;
            int len;
            atom2str(sc,x,(int )pf,&p,&len);
            s_return(sc,mk_counted_string(sc,p,len));
          } else {
            Error_1(sc, "atom->string: not an atom:", x);
          }
        }

     case OP_MKSTRING: { /* make-string */
          int fill=' ';
          int len;

          len=ivalue(car(sc->args));

          if(cdr(sc->args)!=sc->NIL) {
               fill=charvalue(cadr(sc->args));
          }
          s_return(sc,mk_empty_string(sc,len,(char)fill));
     }

     case OP_STRLEN:  /* string-length */
          s_return(sc,mk_integer(sc,strlength(car(sc->args))));

     case OP_STRREF: { /* string-ref */
          char *str;
          int index;

          str=strvalue(car(sc->args));

          index=ivalue(cadr(sc->args));

          if(index>=strlength(car(sc->args))) {
               Error_1(sc,"string-ref: out of bounds:",cadr(sc->args));
          }

          s_return(sc,mk_character(sc,((unsigned char*)str)[index]));
     }

     case OP_STRSET: { /* string-set! */
          char *str;
          int index;
          int c;

          if(is_immutable(car(sc->args))) {
               Error_1(sc,"string-set!: unable to alter immutable string:",car(sc->args));
          }
          str=strvalue(car(sc->args));

          index=ivalue(cadr(sc->args));
          if(index>=strlength(car(sc->args))) {
               Error_1(sc,"string-set!: out of bounds:",cadr(sc->args));
          }

          c=charvalue(caddr(sc->args));

          str[index]=(char)c;
          s_return(sc,car(sc->args));
     }

     case OP_STRAPPEND: { /* string-append */
       /* in 1.29 string-append was in Scheme in init.scm but was too slow */
       int len = 0;
       pointer newstr;
       char *pos;

       /* compute needed length for new string */
       for (x = sc->args; x != sc->NIL; x = cdr(x)) {
          len += strlength(car(x));
       }
       newstr = mk_empty_string(sc, len, ' ');
       /* store the contents of the argument strings into the new string */
       for (pos = strvalue(newstr), x = sc->args; x != sc->NIL;
           pos += strlength(car(x)), x = cdr(x)) {
           memcpy(pos, strvalue(car(x)), strlength(car(x)));
       }
       s_return(sc, newstr);
     }

     case OP_SUBSTR: { /* substring */
          char *str;
          int index0;
          int index1;
          int len;

          str=strvalue(car(sc->args));

          index0=ivalue(cadr(sc->args));

          if(index0>strlength(car(sc->args))) {
               Error_1(sc,"substring: start out of bounds:",cadr(sc->args));
          }

          if(cddr(sc->args)!=sc->NIL) {
               index1=ivalue(caddr(sc->args));
               if(index1>strlength(car(sc->args)) || index1<index0) {
                    Error_1(sc,"substring: end out of bounds:",caddr(sc->args));
               }
          } else {
               index1=strlength(car(sc->args));
          }

          len=index1-index0;
          x=mk_empty_string(sc,len,' ');
          memcpy(strvalue(x),str+index0,len);
          strvalue(x)[len]=0;

          s_return(sc,x);
     }

     case OP_VECTOR: {   /* vector */
          int i;
          pointer vec;
          int len=list_length(sc,sc->args);
          if(len<0) {
               Error_1(sc,"vector: not a proper list:",sc->args);
          }
          vec=mk_vector(sc,len);
          if(sc->no_memory) { s_return(sc, sc->sink); }
          for (x = sc->args, i = 0; is_pair(x); x = cdr(x), i++) {
               set_vector_elem(vec,i,car(x));
          }
          s_return(sc,vec);
     }

     case OP_MKVECTOR: { /* make-vector */
          pointer fill=sc->NIL;
          int len;
          pointer vec;

          len=ivalue(car(sc->args));

          if(cdr(sc->args)!=sc->NIL) {
               fill=cadr(sc->args);
          }
          vec=mk_vector(sc,len);
          if(sc->no_memory) { s_return(sc, sc->sink); }
          if(fill!=sc->NIL) {
               fill_vector(vec,fill);
          }
          s_return(sc,vec);
     }

     case OP_VECLEN:  /* vector-length */
          s_return(sc,mk_integer(sc,ivalue(car(sc->args))));

     case OP_VECREF: { /* vector-ref */
          int index;

          index=ivalue(cadr(sc->args));

          if(index>=ivalue(car(sc->args))) {
               Error_1(sc,"vector-ref: out of bounds:",cadr(sc->args));
          }

          s_return(sc,vector_elem(car(sc->args),index));
     }

     case OP_VECSET: {   /* vector-set! */
          int index;

          if(is_immutable(car(sc->args))) {
               Error_1(sc,"vector-set!: unable to alter immutable vector:",car(sc->args));
          }

          index=ivalue(cadr(sc->args));
          if(index>=ivalue(car(sc->args))) {
               Error_1(sc,"vector-set!: out of bounds:",cadr(sc->args));
          }

          set_vector_elem(car(sc->args),index,caddr(sc->args));
          s_return(sc,car(sc->args));
     }

     default:
          snprintf(sc->strbuff,STRBUFFSIZE,"%d: illegal operator", sc->op);
          Error_0(sc,sc->strbuff);
     }
     return sc->T;
}

static int is_list(scheme *sc, pointer a)
{ return list_length(sc,a) >= 0; }

/* Result is:
   proper list: length
   circular list: -1
   not even a pair: -2
   dotted list: -2 minus length before dot
*/
int list_length(scheme *sc, pointer a) {
    int i=0;
    pointer slow, fast;

    slow = fast = a;
    while (1)
    {
        if (fast == sc->NIL)
                return i;
        if (!is_pair(fast))
                return -2 - i;
        fast = cdr(fast);
        ++i;
        if (fast == sc->NIL)
                return i;
        if (!is_pair(fast))
                return -2 - i;
        ++i;
        fast = cdr(fast);

        /* Safe because we would have already returned if `fast'
           encountered a non-pair. */
        slow = cdr(slow);
        if (fast == slow)
        {
            /* the fast pointer has looped back around and caught up
               with the slow pointer, hence the structure is circular,
               not of finite length, and therefore not a list */
            return -1;
        }
    }
}

static pointer opexe_3(scheme *sc, enum scheme_opcodes op) {
     pointer x;
     num v;
     int (*comp_func)(num,num)=0;

     switch (op) {
     case OP_NOT:        /* not */
          s_retbool(is_false(car(sc->args)));
     case OP_BOOLP:       /* boolean? */
          s_retbool(car(sc->args) == sc->F || car(sc->args) == sc->T);
     case OP_EOFOBJP:       /* boolean? */
          s_retbool(car(sc->args) == sc->EOF_OBJ);
     case OP_NULLP:       /* null? */
          s_retbool(car(sc->args) == sc->NIL);
     case OP_NUMEQ:      /* = */
     case OP_LESS:       /* < */
     case OP_GRE:        /* > */
     case OP_LEQ:        /* <= */
     case OP_GEQ:        /* >= */
          switch(op) {
               case OP_NUMEQ: comp_func=num_eq; break;
               case OP_LESS:  comp_func=num_lt; break;
               case OP_GRE:   comp_func=num_gt; break;
               case OP_LEQ:   comp_func=num_le; break;
               case OP_GEQ:   comp_func=num_ge; break;
          }
          x=sc->args;
          v=nvalue(car(x));
          x=cdr(x);

          for (; x != sc->NIL; x = cdr(x)) {
               if(!comp_func(v,nvalue(car(x)))) {
                    s_retbool(0);
               }
           v=nvalue(car(x));
          }
          s_retbool(1);
     case OP_SYMBOLP:     /* symbol? */
          s_retbool(is_symbol(car(sc->args)));
     case OP_NUMBERP:     /* number? */
          s_retbool(is_number(car(sc->args)));
     case OP_STRINGP:     /* string? */
          s_retbool(is_string(car(sc->args)));
     case OP_INTEGERP:     /* integer? */
          s_retbool(is_integer(car(sc->args)));
     case OP_REALP:     /* real? */
          s_retbool(is_number(car(sc->args))); /* All numbers are real */
     case OP_CHARP:     /* char? */
          s_retbool(is_character(car(sc->args)));
#if USE_CHAR_CLASSIFIERS
     case OP_CHARAP:     /* char-alphabetic? */
          s_retbool(Cisalpha(ivalue(car(sc->args))));
     case OP_CHARNP:     /* char-numeric? */
          s_retbool(Cisdigit(ivalue(car(sc->args))));
     case OP_CHARWP:     /* char-whitespace? */
          s_retbool(Cisspace(ivalue(car(sc->args))));
     case OP_CHARUP:     /* char-upper-case? */
          s_retbool(Cisupper(ivalue(car(sc->args))));
     case OP_CHARLP:     /* char-lower-case? */
          s_retbool(Cislower(ivalue(car(sc->args))));
#endif
     case OP_PORTP:     /* port? */
          s_retbool(is_port(car(sc->args)));
     case OP_INPORTP:     /* input-port? */
          s_retbool(is_inport(car(sc->args)));
     case OP_OUTPORTP:     /* output-port? */
          s_retbool(is_outport(car(sc->args)));
     case OP_PROCP:       /* procedure? */
          /*--
              * continuation should be procedure by the example
              * (call-with-current-continuation procedure?) ==> #t
                 * in R^3 report sec. 6.9
              */
          s_retbool(is_proc(car(sc->args)) || is_closure(car(sc->args))
                 || is_continuation(car(sc->args)) || is_foreign(car(sc->args)));
     case OP_PAIRP:       /* pair? */
          s_retbool(is_pair(car(sc->args)));
     case OP_LISTP:       /* list? */
       s_retbool(list_length(sc,car(sc->args)) >= 0);

     case OP_ENVP:        /* environment? */
          s_retbool(is_environment(car(sc->args)));
     case OP_VECTORP:     /* vector? */
          s_retbool(is_vector(car(sc->args)));
     case OP_EQ:         /* eq? */
          s_retbool(car(sc->args) == cadr(sc->args));
     case OP_EQV:        /* eqv? */
          s_retbool(eqv(car(sc->args), cadr(sc->args)));
     default:
          snprintf(sc->strbuff,STRBUFFSIZE,"%d: illegal operator", sc->op);
          Error_0(sc,sc->strbuff);
     }
     return sc->T;
}

static pointer opexe_4(scheme *sc, enum scheme_opcodes op) {
     pointer x, y;

     switch (op) {
     case OP_FORCE:      /* force */
          sc->code = car(sc->args);
          if (is_promise(sc->code)) {
               /* Should change type to closure here */
               s_save(sc, OP_SAVE_FORCED, sc->NIL, sc->code);
               sc->args = sc->NIL;
               s_goto(sc,OP_APPLY);
          } else {
               s_return(sc,sc->code);
          }

     case OP_SAVE_FORCED:     /* Save forced value replacing promise */
          memcpy(sc->code,sc->value,sizeof(struct cell));
          s_return(sc,sc->value);

     case OP_WRITE:      /* write */
     case OP_DISPLAY:    /* display */
     case OP_WRITE_CHAR: /* write-char */
          if(is_pair(cdr(sc->args))) {
               if(cadr(sc->args)!=sc->outport) {
                    x=cons(sc,sc->outport,sc->NIL);
                    s_save(sc,OP_SET_OUTPORT, x, sc->NIL);
                    sc->outport=cadr(sc->args);
               }
          }
          sc->args = car(sc->args);
          if(op==OP_WRITE) {
               sc->print_flag = 1;
          } else {
               sc->print_flag = 0;
          }
          s_goto(sc,OP_P0LIST);

     case OP_NEWLINE:    /* newline */
          if(is_pair(sc->args)) {
               if(car(sc->args)!=sc->outport) {
                    x=cons(sc,sc->outport,sc->NIL);
                    s_save(sc,OP_SET_OUTPORT, x, sc->NIL);
                    sc->outport=car(sc->args);
               }
          }
          putstr(sc, "\n");
          s_return(sc,sc->T);

     case OP_ERR0:  /* error */
          sc->retcode=-1;
          if (!is_string(car(sc->args))) {
               sc->args=cons(sc,mk_string(sc," -- "),sc->args);
               setimmutable(car(sc->args));
          }
          putstr(sc, "Error: ");
          putstr(sc, strvalue(car(sc->args)));
          sc->args = cdr(sc->args);
          s_goto(sc,OP_ERR1);

     case OP_ERR1:  /* error */
          putstr(sc, " ");
          if (sc->args != sc->NIL) {
               s_save(sc,OP_ERR1, cdr(sc->args), sc->NIL);
               sc->args = car(sc->args);
               sc->print_flag = 1;
               s_goto(sc,OP_P0LIST);
          } else {
               putstr(sc, "\n");
               if(sc->interactive_repl) {
                    s_goto(sc,OP_T0LVL);
               } else {
                    return sc->NIL;
               }
          }

     case OP_REVERSE:   /* reverse */
          s_return(sc,reverse(sc, car(sc->args)));

     case OP_LIST_STAR: /* list* */
          s_return(sc,list_star(sc,sc->args));

     case OP_APPEND:    /* append */
          x = sc->NIL;
          y = sc->args;
          if (y == x) {
              s_return(sc, x);
          }

          /* cdr() in the while condition is not a typo. If car() */
          /* is used (append '() 'a) will return the wrong result.*/
          while (cdr(y) != sc->NIL) {
              x = revappend(sc, x, car(y));
              y = cdr(y);
              if (x == sc->F) {
                  Error_0(sc, "non-list argument to append");
              }
          }

          s_return(sc, reverse_in_place(sc, car(y), x));

#if USE_PLIST
     case OP_PUT:        /* put */
          if (!hasprop(car(sc->args)) || !hasprop(cadr(sc->args))) {
               Error_0(sc,"illegal use of put");
          }
          for (x = symprop(car(sc->args)), y = cadr(sc->args); x != sc->NIL; x = cdr(x)) {
               if (caar(x) == y) {
                    break;
               }
          }
          if (x != sc->NIL)
               cdar(x) = caddr(sc->args);
          else
               symprop(car(sc->args)) = cons(sc, cons(sc, y, caddr(sc->args)),
                                symprop(car(sc->args)));
          s_return(sc,sc->T);

     case OP_GET:        /* get */
          if (!hasprop(car(sc->args)) || !hasprop(cadr(sc->args))) {
               Error_0(sc,"illegal use of get");
          }
          for (x = symprop(car(sc->args)), y = cadr(sc->args); x != sc->NIL; x = cdr(x)) {
               if (caar(x) == y) {
                    break;
               }
          }
          if (x != sc->NIL) {
               s_return(sc,cdar(x));
          } else {
               s_return(sc,sc->NIL);
          }
#endif /* USE_PLIST */
     case OP_QUIT:       /* quit */
          if(is_pair(sc->args)) {
               sc->retcode=ivalue(car(sc->args));
          }
          return (sc->NIL);

     case OP_GC:         /* gc */
          gc(sc, sc->NIL, sc->NIL);
          s_return(sc,sc->T);

     case OP_GCVERB:          /* gc-verbose */
     {    int  was = sc->gc_verbose;

          sc->gc_verbose = (car(sc->args) != sc->F);
          s_retbool(was);
     }

     case OP_NEWSEGMENT: /* new-segment */
          if (!is_pair(sc->args) || !is_number(car(sc->args))) {
               Error_0(sc,"new-segment: argument must be a number");
          }
          alloc_cellseg(sc, (int) ivalue(car(sc->args)));
          s_return(sc,sc->T);

     case OP_OBLIST: /* oblist */
          s_return(sc, oblist_all_symbols(sc));

     case OP_CURR_INPORT: /* current-input-port */
          s_return(sc,sc->inport);

     case OP_CURR_OUTPORT: /* current-output-port */
          s_return(sc,sc->outport);

     case OP_OPEN_INFILE: /* open-input-file */
     case OP_OPEN_OUTFILE: /* open-output-file */
     case OP_OPEN_INOUTFILE: /* open-input-output-file */ {
          int prop=0;
          pointer p;
          switch(op) {
               case OP_OPEN_INFILE:     prop=port_input; break;
               case OP_OPEN_OUTFILE:    prop=port_output; break;
               case OP_OPEN_INOUTFILE: prop=port_input|port_output; break;
          }
          p=port_from_filename(sc,strvalue(car(sc->args)),prop);
          if(p==sc->NIL) {
               s_return(sc,sc->F);
          }
          s_return(sc,p);
     }

#if USE_STRING_PORTS
     case OP_OPEN_INSTRING: /* open-input-string */
     case OP_OPEN_INOUTSTRING: /* open-input-output-string */ {
          int prop=0;
          pointer p;
          switch(op) {
               case OP_OPEN_INSTRING:     prop=port_input; break;
               case OP_OPEN_INOUTSTRING:  prop=port_input|port_output; break;
          }
          p=port_from_string(sc, strvalue(car(sc->args)),
                 strvalue(car(sc->args))+strlength(car(sc->args)), prop);
          if(p==sc->NIL) {
               s_return(sc,sc->F);
          }
          s_return(sc,p);
     }
     case OP_OPEN_OUTSTRING: /* open-output-string */ {
          pointer p;
          if(car(sc->args)==sc->NIL) {
               p=port_from_scratch(sc);
               if(p==sc->NIL) {
                    s_return(sc,sc->F);
               }
          } else {
               p=port_from_string(sc, strvalue(car(sc->args)),
                      strvalue(car(sc->args))+strlength(car(sc->args)),
                          port_output);
               if(p==sc->NIL) {
                    s_return(sc,sc->F);
               }
          }
          s_return(sc,p);
     }
     case OP_GET_OUTSTRING: /* get-output-string */ {
          port *p;

          if ((p=car(sc->args)->_object._port)->kind&port_string) {
               off_t size;
               char *str;

               size=p->rep.string.curr-p->rep.string.start+1;
               str=sc->malloc(size);
               if(str != NULL) {
                    pointer s;

                    memcpy(str,p->rep.string.start,size-1);
                    str[size-1]='\0';
                    s=mk_string(sc,str);
                    sc->free(str);
                    s_return(sc,s);
               }
          }
          s_return(sc,sc->F);
     }
#endif

     case OP_CLOSE_INPORT: /* close-input-port */
          port_close(sc,car(sc->args),port_input);
          s_return(sc,sc->T);

     case OP_CLOSE_OUTPORT: /* close-output-port */
          port_close(sc,car(sc->args),port_output);
          s_return(sc,sc->T);

     case OP_INT_ENV: /* interaction-environment */
          s_return(sc,sc->global_env);

     case OP_CURR_ENV: /* current-environment */
          s_return(sc,sc->envir);

     }
     return sc->T;
}

static pointer opexe_5(scheme *sc, enum scheme_opcodes op) {
     pointer x;

     if(sc->nesting!=0) {
          int n=sc->nesting;
          sc->nesting=0;
          sc->retcode=-1;
          Error_1(sc,"unmatched parentheses:",mk_integer(sc,n));
     }

     switch (op) {
     /* ========== reading part ========== */
     case OP_READ:
          if(!is_pair(sc->args)) {
               s_goto(sc,OP_READ_INTERNAL);
          }
          if(!is_inport(car(sc->args))) {
               Error_1(sc,"read: not an input port:",car(sc->args));
          }
          if(car(sc->args)==sc->inport) {
               s_goto(sc,OP_READ_INTERNAL);
          }
          x=sc->inport;
          sc->inport=car(sc->args);
          x=cons(sc,x,sc->NIL);
          s_save(sc,OP_SET_INPORT, x, sc->NIL);
          s_goto(sc,OP_READ_INTERNAL);

     case OP_READ_CHAR: /* read-char */
     case OP_PEEK_CHAR: /* peek-char */ {
          int c;
          if(is_pair(sc->args)) {
               if(car(sc->args)!=sc->inport) {
                    x=sc->inport;
                    x=cons(sc,x,sc->NIL);
                    s_save(sc,OP_SET_INPORT, x, sc->NIL);
                    sc->inport=car(sc->args);
               }
          }
          c=inchar(sc);
          if(c==EOF) {
               s_return(sc,sc->EOF_OBJ);
          }
          if(sc->op==OP_PEEK_CHAR) {
               backchar(sc,c);
          }
          s_return(sc,mk_character(sc,c));
     }

     case OP_CHAR_READY: /* char-ready? */ {
          pointer p=sc->inport;
          int res;
          if(is_pair(sc->args)) {
               p=car(sc->args);
          }
          res=p->_object._port->kind&port_string;
          s_retbool(res);
     }

     case OP_SET_INPORT: /* set-input-port */
          sc->inport=car(sc->args);
          s_return(sc,sc->value);

     case OP_SET_OUTPORT: /* set-output-port */
          sc->outport=car(sc->args);
          s_return(sc,sc->value);

     case OP_RDSEXPR:
          switch (sc->tok) {
          case TOK_EOF:
               s_return(sc,sc->EOF_OBJ);
          /* NOTREACHED */
/*
 * Commented out because we now skip comments in the scanner
 *
          case TOK_COMMENT: {
               int c;
               while ((c=inchar(sc)) != '\n' && c!=EOF)
                    ;
               sc->tok = token(sc);
               s_goto(sc,OP_RDSEXPR);
          }
*/
          case TOK_VEC:
               s_save(sc,OP_RDVEC,sc->NIL,sc->NIL);
               /* fall through */
          case TOK_LPAREN:
               sc->tok = token(sc);
               if (sc->tok == TOK_RPAREN) {
                    s_return(sc,sc->NIL);
               } else if (sc->tok == TOK_DOT) {
                    Error_0(sc,"syntax error: illegal dot expression");
               } else {
                    sc->nesting_stack[sc->file_i]++;
                    s_save(sc,OP_RDLIST, sc->NIL, sc->NIL);
                    s_goto(sc,OP_RDSEXPR);
               }
          case TOK_QUOTE:
               s_save(sc,OP_RDQUOTE, sc->NIL, sc->NIL);
               sc->tok = token(sc);
               s_goto(sc,OP_RDSEXPR);
          case TOK_BQUOTE:
               sc->tok = token(sc);
               if(sc->tok==TOK_VEC) {
                 s_save(sc,OP_RDQQUOTEVEC, sc->NIL, sc->NIL);
                 sc->tok=TOK_LPAREN;
                 s_goto(sc,OP_RDSEXPR);
               } else {
                 s_save(sc,OP_RDQQUOTE, sc->NIL, sc->NIL);
               }
               s_goto(sc,OP_RDSEXPR);
          case TOK_COMMA:
               s_save(sc,OP_RDUNQUOTE, sc->NIL, sc->NIL);
               sc->tok = token(sc);
               s_goto(sc,OP_RDSEXPR);
          case TOK_ATMARK:
               s_save(sc,OP_RDUQTSP, sc->NIL, sc->NIL);
               sc->tok = token(sc);
               s_goto(sc,OP_RDSEXPR);
          case TOK_ATOM:
               s_return(sc,mk_atom(sc, readstr_upto(sc, DELIMITERS)));
          case TOK_DQUOTE:
               x=readstrexp(sc);
               if(x==sc->F) {
                 Error_0(sc,"Error reading string");
               }
               setimmutable(x);
               s_return(sc,x);
          case TOK_SHARP: {
               pointer f=find_slot_in_env(sc,sc->envir,sc->SHARP_HOOK,1);
               if(f==sc->NIL) {
                    Error_0(sc,"undefined sharp expression");
               } else {
                    sc->code=cons(sc,slot_value_in_env(f),sc->NIL);
                    s_goto(sc,OP_EVAL);
               }
          }
          case TOK_SHARP_CONST:
               if ((x = mk_sharp_const(sc, readstr_upto(sc, DELIMITERS))) == sc->NIL) {
                    Error_0(sc,"undefined sharp expression");
               } else {
                    s_return(sc,x);
               }
          default:
               Error_0(sc,"syntax error: illegal token");
          }
          break;

     case OP_RDLIST: {
          sc->args = cons(sc, sc->value, sc->args);
          sc->tok = token(sc);
/* We now skip comments in the scanner
          while (sc->tok == TOK_COMMENT) {
               int c;
               while ((c=inchar(sc)) != '\n' && c!=EOF)
                    ;
               sc->tok = token(sc);
          }
*/
          if (sc->tok == TOK_EOF)
               { s_return(sc,sc->EOF_OBJ); }
          else if (sc->tok == TOK_RPAREN) {
               int c = inchar(sc);
               if (c != '\n')
                 backchar(sc,c);
#if SHOW_ERROR_LINE
               else if (sc->load_stack[sc->file_i].kind & port_file)
                  sc->load_stack[sc->file_i].rep.stdio.curr_line++;
#endif
               sc->nesting_stack[sc->file_i]--;
               s_return(sc,reverse_in_place(sc, sc->NIL, sc->args));
          } else if (sc->tok == TOK_DOT) {
               s_save(sc,OP_RDDOT, sc->args, sc->NIL);
               sc->tok = token(sc);
               s_goto(sc,OP_RDSEXPR);
          } else {
               s_save(sc,OP_RDLIST, sc->args, sc->NIL);;
               s_goto(sc,OP_RDSEXPR);
          }
     }

     case OP_RDDOT:
          if (token(sc) != TOK_RPAREN) {
               Error_0(sc,"syntax error: illegal dot expression");
          } else {
               sc->nesting_stack[sc->file_i]--;
               s_return(sc,reverse_in_place(sc, sc->value, sc->args));
          }

     case OP_RDQUOTE:
          s_return(sc,cons(sc, sc->QUOTE, cons(sc, sc->value, sc->NIL)));

     case OP_RDQQUOTE:
          s_return(sc,cons(sc, sc->QQUOTE, cons(sc, sc->value, sc->NIL)));

     case OP_RDQQUOTEVEC:
           s_return(sc,cons(sc, mk_symbol(sc,"apply"),
           cons(sc, mk_symbol(sc,"vector"),
                 cons(sc,cons(sc, sc->QQUOTE,
                  cons(sc,sc->value,sc->NIL)),
                  sc->NIL))));

     case OP_RDUNQUOTE:
          s_return(sc,cons(sc, sc->UNQUOTE, cons(sc, sc->value, sc->NIL)));

     case OP_RDUQTSP:
          s_return(sc,cons(sc, sc->UNQUOTESP, cons(sc, sc->value, sc->NIL)));

     case OP_RDVEC:
          /*sc->code=cons(sc,mk_proc(sc,OP_VECTOR),sc->value);
          s_goto(sc,OP_EVAL); Cannot be quoted*/
          /*x=cons(sc,mk_proc(sc,OP_VECTOR),sc->value);
          s_return(sc,x); Cannot be part of pairs*/
          /*sc->code=mk_proc(sc,OP_VECTOR);
          sc->args=sc->value;
          s_goto(sc,OP_APPLY);*/
          sc->args=sc->value;
          s_goto(sc,OP_VECTOR);

     /* ========== printing part ========== */
     case OP_P0LIST:
          if(is_vector(sc->args)) {
               putstr(sc,"#(");
               sc->args=cons(sc,sc->args,mk_integer(sc,0));
               s_goto(sc,OP_PVECFROM);
          } else if(is_environment(sc->args)) {
               putstr(sc,"#<ENVIRONMENT>");
               s_return(sc,sc->T);
          } else if (!is_pair(sc->args)) {
               printatom(sc, sc->args, sc->print_flag);
               s_return(sc,sc->T);
          } else if (car(sc->args) == sc->QUOTE && ok_abbrev(cdr(sc->args))) {
               putstr(sc, "'");
               sc->args = cadr(sc->args);
               s_goto(sc,OP_P0LIST);
          } else if (car(sc->args) == sc->QQUOTE && ok_abbrev(cdr(sc->args))) {
               putstr(sc, "`");
               sc->args = cadr(sc->args);
               s_goto(sc,OP_P0LIST);
          } else if (car(sc->args) == sc->UNQUOTE && ok_abbrev(cdr(sc->args))) {
               putstr(sc, ",");
               sc->args = cadr(sc->args);
               s_goto(sc,OP_P0LIST);
          } else if (car(sc->args) == sc->UNQUOTESP && ok_abbrev(cdr(sc->args))) {
               putstr(sc, ",@");
               sc->args = cadr(sc->args);
               s_goto(sc,OP_P0LIST);
          } else {
               putstr(sc, "(");
               s_save(sc,OP_P1LIST, cdr(sc->args), sc->NIL);
               sc->args = car(sc->args);
               s_goto(sc,OP_P0LIST);
          }

     case OP_P1LIST:
          if (is_pair(sc->args)) {
            s_save(sc,OP_P1LIST, cdr(sc->args), sc->NIL);
            putstr(sc, " ");
            sc->args = car(sc->args);
            s_goto(sc,OP_P0LIST);
          } else if(is_vector(sc->args)) {
            s_save(sc,OP_P1LIST,sc->NIL,sc->NIL);
            putstr(sc, " . ");
            s_goto(sc,OP_P0LIST);
          } else {
            if (sc->args != sc->NIL) {
              putstr(sc, " . ");
              printatom(sc, sc->args, sc->print_flag);
            }
            putstr(sc, ")");
            s_return(sc,sc->T);
          }
     case OP_PVECFROM: {
          int i=ivalue_unchecked(cdr(sc->args));
          pointer vec=car(sc->args);
          int len=ivalue_unchecked(vec);
          if(i==len) {
               putstr(sc,")");
               s_return(sc,sc->T);
          } else {
               pointer elem=vector_elem(vec,i);
               ivalue_unchecked(cdr(sc->args))=i+1;
               s_save(sc,OP_PVECFROM, sc->args, sc->NIL);
               sc->args=elem;
               if (i > 0)
                   putstr(sc," ");
               s_goto(sc,OP_P0LIST);
          }
     }

     default:
          snprintf(sc->strbuff,STRBUFFSIZE,"%d: illegal operator", sc->op);
          Error_0(sc,sc->strbuff);

     }
     return sc->T;
}

static pointer opexe_6(scheme *sc, enum scheme_opcodes op) {
     pointer x, y;
     long v;

     switch (op) {
     case OP_LIST_LENGTH:     /* length */   /* a.k */
          v=list_length(sc,car(sc->args));
          if(v<0) {
               Error_1(sc,"length: not a list:",car(sc->args));
          }
          s_return(sc,mk_integer(sc, v));

     case OP_ASSQ:       /* assq */     /* a.k */
          x = car(sc->args);
          for (y = cadr(sc->args); is_pair(y); y = cdr(y)) {
               if (!is_pair(car(y))) {
                    Error_0(sc,"unable to handle non pair element");
               }
               if (x == caar(y))
                    break;
          }
          if (is_pair(y)) {
               s_return(sc,car(y));
          } else {
               s_return(sc,sc->F);
          }


     case OP_GET_CLOSURE:     /* get-closure-code */   /* a.k */
          sc->args = car(sc->args);
          if (sc->args == sc->NIL) {
               s_return(sc,sc->F);
          } else if (is_closure(sc->args)) {
               s_return(sc,cons(sc, sc->LAMBDA, closure_code(sc->value)));
          } else if (is_macro(sc->args)) {
               s_return(sc,cons(sc, sc->LAMBDA, closure_code(sc->value)));
          } else {
               s_return(sc,sc->F);
          }
     case OP_CLOSUREP:        /* closure? */
          /*
           * Note, macro object is also a closure.
           * Therefore, (closure? <#MACRO>) ==> #t
           */
          s_retbool(is_closure(car(sc->args)));
     case OP_MACROP:          /* macro? */
          s_retbool(is_macro(car(sc->args)));
     default:
          snprintf(sc->strbuff,STRBUFFSIZE,"%d: illegal operator", sc->op);
          Error_0(sc,sc->strbuff);
     }
     return sc->T; /* NOTREACHED */
}

typedef pointer (*dispatch_func)(scheme *, enum scheme_opcodes);

typedef int (*test_predicate)(pointer);
static int is_any(pointer p) { return 1;}

static int is_nonneg(pointer p) {
  return ivalue(p)>=0 && is_integer(p);
}

/* Correspond carefully with following defines! */
static struct {
  test_predicate fct;
  const char *kind;
} tests[]={
  {0,0}, /* unused */
  {is_any, 0},
  {is_string, "string"},
  {is_symbol, "symbol"},
  {is_port, "port"},
  {is_inport,"input port"},
  {is_outport,"output port"},
  {is_environment, "environment"},
  {is_pair, "pair"},
  {0, "pair or '()"},
  {is_character, "character"},
  {is_vector, "vector"},
  {is_number, "number"},
  {is_integer, "integer"},
  {is_nonneg, "non-negative integer"}
};

#define TST_NONE 0
#define TST_ANY "\001"
#define TST_STRING "\002"
#define TST_SYMBOL "\003"
#define TST_PORT "\004"
#define TST_INPORT "\005"
#define TST_OUTPORT "\006"
#define TST_ENVIRONMENT "\007"
#define TST_PAIR "\010"
#define TST_LIST "\011"
#define TST_CHAR "\012"
#define TST_VECTOR "\013"
#define TST_NUMBER "\014"
#define TST_INTEGER "\015"
#define TST_NATURAL "\016"

typedef struct {
  dispatch_func func;
  char *name;
  int min_arity;
  int max_arity;
  char *arg_tests_encoding;
} op_code_info;

#define INF_ARG 0xffff

static op_code_info dispatch_table[]= {
#define _OP_DEF(A,B,C,D,E,OP) {A,B,C,D,E},
#include "opdefines.h"
  { 0 }
};

static const char *procname(pointer x) {
 int n=procnum(x);
 const char *name=dispatch_table[n].name;
 if(name==0) {
     name="ILLEGAL!";
 }
 return name;
}

/* kernel of this interpreter */
static void Eval_Cycle(scheme *sc, enum scheme_opcodes op) {
  sc->op = op;
  for (;;) {
    op_code_info *pcd=dispatch_table+sc->op;
    if (pcd->name!=0) { /* if built-in function, check arguments */
      char msg[STRBUFFSIZE];
      int ok=1;
      int n=list_length(sc,sc->args);

      /* Check number of arguments */
      if(n<pcd->min_arity) {
        ok=0;
        snprintf(msg, STRBUFFSIZE, "%s: needs%s %d argument(s)",
        pcd->name,
        pcd->min_arity==pcd->max_arity?"":" at least",
        pcd->min_arity);
      }
      if(ok && n>pcd->max_arity) {
        ok=0;
        snprintf(msg, STRBUFFSIZE, "%s: needs%s %d argument(s)",
        pcd->name,
        pcd->min_arity==pcd->max_arity?"":" at most",
        pcd->max_arity);
      }
      if(ok) {
        if(pcd->arg_tests_encoding!=0) {
          int i=0;
          int j;
          const char *t=pcd->arg_tests_encoding;
          pointer arglist=sc->args;
          do {
            pointer arg=car(arglist);
            j=(int)t[0];
            if(j==TST_LIST[0]) {
                  if(arg!=sc->NIL && !is_pair(arg)) break;
            } else {
              if(!tests[j].fct(arg)) break;
            }

            if(t[1]!=0) {/* last test is replicated as necessary */
              t++;
            }
            arglist=cdr(arglist);
            i++;
          } while(i<n);
          if(i<n) {
            ok=0;
            snprintf(msg, STRBUFFSIZE, "%s: argument %d must be: %s",
                pcd->name,
                i+1,
                tests[j].kind);
          }
        }
      }
      if(!ok) {
        if(_Error_1(sc,msg,0)==sc->NIL) {
          return;
        }
        pcd=dispatch_table+sc->op;
      }
    }
    ok_to_freely_gc(sc);
    if (pcd->func(sc, (enum scheme_opcodes)sc->op) == sc->NIL) {
      return;
    }
    if(sc->no_memory) {
      fprintf(stderr,"No memory!\n");
      return;
    }
  }
}

/* ========== Initialization of internal keywords ========== */

static void assign_syntax(scheme *sc, char *name) {
     pointer x;

     x = oblist_add_by_name(sc, name);
     typeflag(x) |= T_SYNTAX;
}

static void assign_proc(scheme *sc, enum scheme_opcodes op, char *name) {
     pointer x, y;

     x = mk_symbol(sc, name);
     y = mk_proc(sc,op);
     new_slot_in_env(sc, x, y);
}

static pointer mk_proc(scheme *sc, enum scheme_opcodes op) {
     pointer y;

     y = get_cell(sc, sc->NIL, sc->NIL);
     typeflag(y) = (T_PROC | T_ATOM);
     ivalue_unchecked(y) = (long) op;
     set_num_integer(y);
     return y;
}

/* Hard-coded for the given keywords. Remember to rewrite if more are added! */
static int syntaxnum(pointer p) {
     const char *s=strvalue(car(p));
     switch(strlength(car(p))) {
     case 2:
          if(s[0]=='i') return OP_IF0;        /* if */
          else return OP_OR0;                 /* or */
     case 3:
          if(s[0]=='a') return OP_AND0;      /* and */
          else return OP_LET0;               /* let */
     case 4:
          switch(s[3]) {
          case 'e': return OP_CASE0;         /* case */
          case 'd': return OP_COND0;         /* cond */
          case '*': return OP_LET0AST;       /* let* */
          default: return OP_SET0;           /* set! */
          }
     case 5:
          switch(s[2]) {
          case 'g': return OP_BEGIN;         /* begin */
          case 'l': return OP_DELAY;         /* delay */
          case 'c': return OP_MACRO0;        /* macro */
          default: return OP_QUOTE;          /* quote */
          }
     case 6:
          switch(s[2]) {
          case 'm': return OP_LAMBDA;        /* lambda */
          case 'f': return OP_DEF0;          /* define */
          default: return OP_LET0REC;        /* letrec */
          }
     default:
          return OP_C0STREAM;                /* cons-stream */
     }
}

/* initialization of TinyScheme */
#if USE_INTERFACE
INTERFACE static pointer s_cons(scheme *sc, pointer a, pointer b) {
 return cons(sc,a,b);
}
INTERFACE static pointer s_immutable_cons(scheme *sc, pointer a, pointer b) {
 return immutable_cons(sc,a,b);
}

static struct scheme_interface vtbl ={
  scheme_define,
  s_cons,
  s_immutable_cons,
  reserve_cells,
  mk_integer,
  mk_real,
  mk_symbol,
  gensym,
  mk_string,
  mk_counted_string,
  mk_character,
  mk_vector,
  mk_foreign_func,
  putstr,
  putcharacter,

  is_string,
  string_value,
  is_number,
  nvalue,
  ivalue,
  rvalue,
  is_integer,
  is_real,
  is_character,
  charvalue,
  is_list,
  is_vector,
  list_length,
  ivalue,
  fill_vector,
  vector_elem,
  set_vector_elem,
  is_port,
  is_pair,
  pair_car,
  pair_cdr,
  set_car,
  set_cdr,

  is_symbol,
  symname,

  is_syntax,
  is_proc,
  is_foreign,
  syntaxname,
  is_closure,
  is_macro,
  closure_code,
  closure_env,

  is_continuation,
  is_promise,
  is_environment,
  is_immutable,
  setimmutable,

  scheme_load_file,
  scheme_load_string
};
#endif

scheme *scheme_init_new() {
  scheme *sc=(scheme*)malloc(sizeof(scheme));
  if(!scheme_init(sc)) {
    free(sc);
    return 0;
  } else {
    return sc;
  }
}

scheme *scheme_init_new_custom_alloc(func_alloc malloc, func_dealloc free) {
  scheme *sc=(scheme*)malloc(sizeof(scheme));
  if(!scheme_init_custom_alloc(sc,malloc,free)) {
    free(sc);
    return 0;
  } else {
    return sc;
  }
}


int scheme_init(scheme *sc) {
 return scheme_init_custom_alloc(sc,malloc,free);
}

int scheme_init_custom_alloc(scheme *sc, func_alloc malloc, func_dealloc free) {
  int i, n=sizeof(dispatch_table)/sizeof(dispatch_table[0]);
  pointer x;

  /* fix unitialized free under Mac OS X */
  memset( sc->load_stack, 0, sizeof(port) * MAXFIL );

  num_zero.is_fixnum=1;
  num_zero.value.ivalue=0;
  num_one.is_fixnum=1;
  num_one.value.ivalue=1;

#if USE_INTERFACE
  sc->vptr=&vtbl;
#endif
  sc->gensym_cnt=0;
  sc->malloc=malloc;
  sc->free=free;
  sc->last_cell_seg = -1;
  sc->sink = &sc->_sink;
  sc->NIL = &sc->_NIL;
  sc->T = &sc->_HASHT;
  sc->F = &sc->_HASHF;
  sc->EOF_OBJ=&sc->_EOF_OBJ;
  sc->free_cell = &sc->_NIL;
  sc->fcells = 0;
  sc->no_memory=0;
  sc->inport=sc->NIL;
  sc->outport=sc->NIL;
  sc->save_inport=sc->NIL;
  sc->loadport=sc->NIL;
  sc->nesting=0;
  sc->interactive_repl=0;

  if (alloc_cellseg(sc,FIRST_CELLSEGS) != FIRST_CELLSEGS) {
    sc->no_memory=1;
    return 0;
  }
  sc->gc_verbose = 0;
  dump_stack_initialize(sc);
  sc->code = sc->NIL;
  sc->tracing=0;

  /* init sc->NIL */
  typeflag(sc->NIL) = (T_ATOM | MARK);
  car(sc->NIL) = cdr(sc->NIL) = sc->NIL;
  /* init T */
  typeflag(sc->T) = (T_ATOM | MARK);
  car(sc->T) = cdr(sc->T) = sc->T;
  /* init F */
  typeflag(sc->F) = (T_ATOM | MARK);
  car(sc->F) = cdr(sc->F) = sc->F;
  /* init sink */
  typeflag(sc->sink) = (T_PAIR | MARK);
  car(sc->sink) = sc->NIL;
  /* init c_nest */
  sc->c_nest = sc->NIL;

  sc->oblist = oblist_initial_value(sc);
  /* init global_env */
  new_frame_in_env(sc, sc->NIL);
  sc->global_env = sc->envir;
  /* init else */
  x = mk_symbol(sc,"else");
  new_slot_in_env(sc, x, sc->T);

  assign_syntax(sc, "lambda");
  assign_syntax(sc, "quote");
  assign_syntax(sc, "define");
  assign_syntax(sc, "if");
  assign_syntax(sc, "begin");
  assign_syntax(sc, "set!");
  assign_syntax(sc, "let");
  assign_syntax(sc, "let*");
  assign_syntax(sc, "letrec");
  assign_syntax(sc, "cond");
  assign_syntax(sc, "delay");
  assign_syntax(sc, "and");
  assign_syntax(sc, "or");
  assign_syntax(sc, "cons-stream");
  assign_syntax(sc, "macro");
  assign_syntax(sc, "case");

  for(i=0; i<n; i++) {
    if(dispatch_table[i].name!=0) {
      assign_proc(sc, (enum scheme_opcodes)i, dispatch_table[i].name);
    }
  }

  /* initialization of global pointers to special symbols */
  sc->LAMBDA = mk_symbol(sc, "lambda");
  sc->QUOTE = mk_symbol(sc, "quote");
  sc->QQUOTE = mk_symbol(sc, "quasiquote");
  sc->UNQUOTE = mk_symbol(sc, "unquote");
  sc->UNQUOTESP = mk_symbol(sc, "unquote-splicing");
  sc->FEED_TO = mk_symbol(sc, "=>");
  sc->COLON_HOOK = mk_symbol(sc,"*colon-hook*");
  sc->ERROR_HOOK = mk_symbol(sc, "*error-hook*");
  sc->SHARP_HOOK = mk_symbol(sc, "*sharp-hook*");
  sc->COMPILE_HOOK = mk_symbol(sc, "*compile-hook*");

  return !sc->no_memory;
}

void scheme_set_input_port_file(scheme *sc, FILE *fin) {
  sc->inport=port_from_file(sc,fin,port_input);
}

void scheme_set_input_port_string(scheme *sc, char *start, char *past_the_end) {
  sc->inport=port_from_string(sc,start,past_the_end,port_input);
}

void scheme_set_output_port_file(scheme *sc, FILE *fout) {
  sc->outport=port_from_file(sc,fout,port_output);
}

void scheme_set_output_port_string(scheme *sc, char *start, char *past_the_end) {
  sc->outport=port_from_string(sc,start,past_the_end,port_output);
}

void scheme_set_external_data(scheme *sc, void *p) {
 sc->ext_data=p;
}

void scheme_deinit(scheme *sc) {
  int i;

#if SHOW_ERROR_LINE
  char *fname;
#endif

  sc->oblist=sc->NIL;
  sc->global_env=sc->NIL;
  dump_stack_free(sc);
  sc->envir=sc->NIL;
  sc->code=sc->NIL;
  sc->args=sc->NIL;
  sc->value=sc->NIL;
  if(is_port(sc->inport)) {
    typeflag(sc->inport) = T_ATOM;
  }
  sc->inport=sc->NIL;
  sc->outport=sc->NIL;
  if(is_port(sc->save_inport)) {
    typeflag(sc->save_inport) = T_ATOM;
  }
  sc->save_inport=sc->NIL;
  if(is_port(sc->loadport)) {
    typeflag(sc->loadport) = T_ATOM;
  }
  sc->loadport=sc->NIL;
  sc->gc_verbose=0;
  gc(sc,sc->NIL,sc->NIL);

  for(i=0; i<=sc->last_cell_seg; i++) {
    sc->free(sc->alloc_seg[i]);
  }

#if SHOW_ERROR_LINE
  for(i=0; i<=sc->file_i; i++) {
    if (sc->load_stack[i].kind & port_file) {
      fname = sc->load_stack[i].rep.stdio.filename;
      if(fname)
        sc->free(fname);
    }
  }
#endif
}

void scheme_load_file(scheme *sc, FILE *fin)
{ scheme_load_named_file(sc,fin,0); }

void scheme_load_named_file(scheme *sc, FILE *fin, const char *filename) {
  int interactive_repl = sc->interactive_repl && !filename;
  dump_stack_reset(sc);
  sc->envir = sc->global_env;
  sc->file_i=0;
  sc->load_stack[0].kind=port_input|port_file;
  sc->load_stack[0].rep.stdio.file=fin;
  sc->load_stack[0].rep.stdio.interactive=interactive_repl;
  sc->loadport=mk_port(sc,sc->load_stack);
  sc->retcode=0;
  if(interactive_repl) {
    sc->interactive_repl=interactive_repl;
  }

#if SHOW_ERROR_LINE
  sc->load_stack[0].rep.stdio.curr_line = 0;
  if(fin!=stdin && filename)
    sc->load_stack[0].rep.stdio.filename = store_string(sc, strlen(filename), filename, 0);
#endif

  sc->inport=sc->loadport;
  sc->args = mk_integer(sc,sc->file_i);
  Eval_Cycle(sc, OP_T0LVL);
  typeflag(sc->loadport)=T_ATOM;
  if(sc->retcode==0) {
    sc->retcode=sc->nesting!=0;
  }
}

void scheme_load_string(scheme *sc, const char *cmd) {
  dump_stack_reset(sc);
  sc->envir = sc->global_env;
  sc->file_i=0;
  sc->load_stack[0].kind=port_input|port_string;
  sc->load_stack[0].rep.string.start=(char*)cmd; /* This func respects const */
  sc->load_stack[0].rep.string.past_the_end=(char*)cmd+strlen(cmd);
  sc->load_stack[0].rep.string.curr=(char*)cmd;
  sc->loadport=mk_port(sc,sc->load_stack);
  sc->retcode=0;
  sc->interactive_repl=0;
  sc->inport=sc->loadport;
  sc->args = mk_integer(sc,sc->file_i);
  Eval_Cycle(sc, OP_T0LVL);
  typeflag(sc->loadport)=T_ATOM;
  if(sc->retcode==0) {
    sc->retcode=sc->nesting!=0;
  }
}

void scheme_define(scheme *sc, pointer envir, pointer symbol, pointer value) {
     pointer x;

     x=find_slot_in_env(sc,envir,symbol,0);
     if (x != sc->NIL) {
          set_slot_in_env(sc, x, value);
     } else {
          new_slot_spec_in_env(sc, envir, symbol, value);
     }
}

#if !STANDALONE
void scheme_register_foreign_func(scheme * sc, scheme_registerable * sr)
{
  scheme_define(sc,
                sc->global_env,
                mk_symbol(sc,sr->name),
                mk_foreign_func(sc, sr->f));
}

void scheme_register_foreign_func_list(scheme * sc,
                                       scheme_registerable * list,
                                       int count)
{
  int i;
  for(i = 0; i < count; i++)
    {
      scheme_register_foreign_func(sc, list + i);
    }
}

pointer scheme_apply0(scheme *sc, const char *procname)
{ return scheme_eval(sc, cons(sc,mk_symbol(sc,procname),sc->NIL)); }

void save_from_C_call(scheme *sc)
{
  pointer saved_data =
    cons(sc,
         car(sc->sink),
         cons(sc,
              sc->envir,
              sc->dump));
  /* Push */
  sc->c_nest = cons(sc, saved_data, sc->c_nest);
  /* Truncate the dump stack so TS will return here when done, not
     directly resume pre-C-call operations. */
  dump_stack_reset(sc);
}
void restore_from_C_call(scheme *sc)
{
  car(sc->sink) = caar(sc->c_nest);
  sc->envir = cadar(sc->c_nest);
  sc->dump = cdr(cdar(sc->c_nest));
  /* Pop */
  sc->c_nest = cdr(sc->c_nest);
}

/* "func" and "args" are assumed to be already eval'ed. */
pointer scheme_call(scheme *sc, pointer func, pointer args)
{
  int old_repl = sc->interactive_repl;
  sc->interactive_repl = 0;
  save_from_C_call(sc);
  sc->envir = sc->global_env;
  sc->args = args;
  sc->code = func;
  sc->retcode = 0;
  Eval_Cycle(sc, OP_APPLY);
  sc->interactive_repl = old_repl;
  restore_from_C_call(sc);
  return sc->value;
}

pointer scheme_eval(scheme *sc, pointer obj)
{
  int old_repl = sc->interactive_repl;
  sc->interactive_repl = 0;
  save_from_C_call(sc);
  sc->args = sc->NIL;
  sc->code = obj;
  sc->retcode = 0;
  Eval_Cycle(sc, OP_EVAL);
  sc->interactive_repl = old_repl;
  restore_from_C_call(sc);
  return sc->value;
}


#endif

/* ========== Main ========== */

#if STANDALONE

int main(int argc, char **argv) {
  scheme sc;
  FILE *fin;
  char *file_name=InitFile;
  int retcode;
  int isfile=1;

  if(argc==1) {
    printf(banner);
  }
  if(argc==2 && strcmp(argv[1],"-?")==0) {
    printf("Usage: tinyscheme -?\n");
    printf("or:    tinyscheme [<file1> <file2> ...]\n");
    printf("followed by\n");
    printf("          -1 <file> [<arg1> <arg2> ...]\n");
    printf("          -c <Scheme commands> [<arg1> <arg2> ...]\n");
    printf("assuming that the executable is named tinyscheme.\n");
    printf("Use - as filename for stdin.\n");
    return 1;
  }
  if(!scheme_init(&sc)) {
    fprintf(stderr,"Could not initialize!\n");
    return 2;
  }
  scheme_set_input_port_file(&sc, stdin);
  scheme_set_output_port_file(&sc, stdout);
  argv++;
  if(access(file_name,0)!=0) {
    char *p=getenv("TINYSCHEMEINIT");
    if(p!=0) {
      file_name=p;
    }
  }
  do {
    if(strcmp(file_name,"-")==0) {
      fin=stdin;
    } else if(strcmp(file_name,"-1")==0 || strcmp(file_name,"-c")==0) {
      pointer args=sc.NIL;
      isfile=file_name[1]=='1';
      file_name=*argv++;
      if(strcmp(file_name,"-")==0) {
        fin=stdin;
      } else if(isfile) {
        fin=fopen(file_name,"r");
      }
      for(;*argv;argv++) {
        pointer value=mk_string(&sc,*argv);
        args=cons(&sc,value,args);
      }
      args=reverse_in_place(&sc,sc.NIL,args);
      scheme_define(&sc,sc.global_env,mk_symbol(&sc,"*args*"),args);

    } else {
      fin=fopen(file_name,"r");
    }
    if(isfile && fin==0) {
      fprintf(stderr,"Could not open file %s\n",file_name);
    } else {
      if(isfile) {
        scheme_load_named_file(&sc,fin,file_name);
      } else {
        scheme_load_string(&sc,file_name);
      }
      if(!isfile || fin!=stdin) {
        if(sc.retcode!=0) {
          fprintf(stderr,"Errors encountered reading %s\n",file_name);
        }
        if(isfile) {
          fclose(fin);
        }
      }
    }
    file_name=*argv++;
  } while(file_name!=0);
  if(argc==1) {
    scheme_load_named_file(&sc,stdin,0);
  }
  retcode=sc.retcode;
  scheme_deinit(&sc);

  return retcode;
}

#endif

-
+ FF0B30C650A38189BE4BB174A60143D1EA61061BC56838B49CBE63190CA0FCC15409E7CE7540B2A433EDE6BB1DFE97BAA901FDEA86D480224A36B69519E94171
bitcoin/src/shiva/scheme.h

(0 . 0)(1 . 253)
/* SCHEME.H */

#ifndef _SCHEME_H
#define _SCHEME_H

#include "scheme-knobs.h"

#define PACKAGE_VERSION "TRB"

#include <stdio.h>

#ifdef __cplusplus
extern "C" {
#endif

/*
 * Default values for #define'd symbols
 */
#ifndef STANDALONE       /* If used as standalone interpreter */
# define STANDALONE 1
#endif

#ifndef _MSC_VER
# define USE_STRCASECMP 1
# ifndef USE_STRLWR
#   define USE_STRLWR 1
# endif
# define SCHEME_EXPORT
#else
# define USE_STRCASECMP 0
# define USE_STRLWR 0
# ifdef _SCHEME_SOURCE
#  define SCHEME_EXPORT __declspec(dllexport)
# else
#  define SCHEME_EXPORT __declspec(dllimport)
# endif
#endif

#if USE_NO_FEATURES
# define USE_MATH 0
# define USE_CHAR_CLASSIFIERS 0
# define USE_ASCII_NAMES 0
# define USE_STRING_PORTS 0
# define USE_ERROR_HOOK 0
# define USE_TRACING 0
# define USE_COLON_HOOK 0
# define USE_PLIST 0
#endif

/*
 * Leave it defined if you want continuations, and also for the Sharp Zaurus.
 * Undefine it if you only care about faster speed and not strict Scheme compatibility.
 */
#define USE_SCHEME_STACK

#ifndef USE_MATH         /* If math support is needed */
# define USE_MATH 1
#endif

#ifndef USE_CHAR_CLASSIFIERS  /* If char classifiers are needed */
# define USE_CHAR_CLASSIFIERS 1
#endif

#ifndef USE_ASCII_NAMES  /* If extended escaped characters are needed */
# define USE_ASCII_NAMES 1
#endif

#ifndef USE_STRING_PORTS      /* Enable string ports */
# define USE_STRING_PORTS 1
#endif

#ifndef USE_TRACING
# define USE_TRACING 1
#endif

#ifndef USE_PLIST
# define USE_PLIST 0
#endif

/* To force system errors through user-defined error handling (see *error-hook*) */
#ifndef USE_ERROR_HOOK
# define USE_ERROR_HOOK 1
#endif

#ifndef USE_COLON_HOOK   /* Enable qualified qualifier */
# define USE_COLON_HOOK 1
#endif

#ifndef USE_STRCASECMP   /* stricmp for Unix */
# define USE_STRCASECMP 0
#endif

#ifndef USE_STRLWR
# define USE_STRLWR 1
#endif

#ifndef STDIO_ADDS_CR    /* Define if DOS/Windows */
# define STDIO_ADDS_CR 0
#endif

#ifndef INLINE
# define INLINE
#endif

#ifndef USE_INTERFACE
# define USE_INTERFACE 0
#endif

#ifndef SHOW_ERROR_LINE   /* Show error line in file */
# define SHOW_ERROR_LINE 1
#endif

typedef struct scheme scheme;
typedef struct cell *pointer;

typedef void * (*func_alloc)(size_t);
typedef void (*func_dealloc)(void *);

/* num, for generic arithmetic */
typedef struct num {
     char is_fixnum;
     union {
          long ivalue;
          double rvalue;
     } value;
} num;

SCHEME_EXPORT scheme *scheme_init_new();
SCHEME_EXPORT scheme *scheme_init_new_custom_alloc(func_alloc malloc, func_dealloc free);
SCHEME_EXPORT int scheme_init(scheme *sc);
SCHEME_EXPORT int scheme_init_custom_alloc(scheme *sc, func_alloc, func_dealloc);
SCHEME_EXPORT void scheme_deinit(scheme *sc);
void scheme_set_input_port_file(scheme *sc, FILE *fin);
void scheme_set_input_port_string(scheme *sc, char *start, char *past_the_end);
SCHEME_EXPORT void scheme_set_output_port_file(scheme *sc, FILE *fin);
void scheme_set_output_port_string(scheme *sc, char *start, char *past_the_end);
SCHEME_EXPORT void scheme_load_file(scheme *sc, FILE *fin);
SCHEME_EXPORT void scheme_load_named_file(scheme *sc, FILE *fin, const char *filename);
SCHEME_EXPORT void scheme_load_string(scheme *sc, const char *cmd);
SCHEME_EXPORT pointer scheme_apply0(scheme *sc, const char *procname);
SCHEME_EXPORT pointer scheme_call(scheme *sc, pointer func, pointer args);
SCHEME_EXPORT pointer scheme_eval(scheme *sc, pointer obj);
void scheme_set_external_data(scheme *sc, void *p);
SCHEME_EXPORT void scheme_define(scheme *sc, pointer env, pointer symbol, pointer value);

typedef pointer (*foreign_func)(scheme *, pointer);

pointer _cons(scheme *sc, pointer a, pointer b, int immutable);
pointer mk_integer(scheme *sc, long num);
pointer mk_real(scheme *sc, double num);
pointer mk_symbol(scheme *sc, const char *name);
pointer gensym(scheme *sc);
pointer mk_string(scheme *sc, const char *str);
pointer mk_counted_string(scheme *sc, const char *str, int len);
pointer mk_empty_string(scheme *sc, int len, char fill);
pointer mk_character(scheme *sc, int c);
pointer mk_foreign_func(scheme *sc, foreign_func f);
void putstr(scheme *sc, const char *s);
int list_length(scheme *sc, pointer a);
int eqv(pointer a, pointer b);


#if USE_INTERFACE
struct scheme_interface {
  void (*scheme_define)(scheme *sc, pointer env, pointer symbol, pointer value);
  pointer (*cons)(scheme *sc, pointer a, pointer b);
  pointer (*immutable_cons)(scheme *sc, pointer a, pointer b);
  pointer (*reserve_cells)(scheme *sc, int n);
  pointer (*mk_integer)(scheme *sc, long num);
  pointer (*mk_real)(scheme *sc, double num);
  pointer (*mk_symbol)(scheme *sc, const char *name);
  pointer (*gensym)(scheme *sc);
  pointer (*mk_string)(scheme *sc, const char *str);
  pointer (*mk_counted_string)(scheme *sc, const char *str, int len);
  pointer (*mk_character)(scheme *sc, int c);
  pointer (*mk_vector)(scheme *sc, int len);
  pointer (*mk_foreign_func)(scheme *sc, foreign_func f);
  void (*putstr)(scheme *sc, const char *s);
  void (*putcharacter)(scheme *sc, int c);

  int (*is_string)(pointer p);
  char *(*string_value)(pointer p);
  int (*is_number)(pointer p);
  num (*nvalue)(pointer p);
  long (*ivalue)(pointer p);
  double (*rvalue)(pointer p);
  int (*is_integer)(pointer p);
  int (*is_real)(pointer p);
  int (*is_character)(pointer p);
  long (*charvalue)(pointer p);
  int (*is_list)(scheme *sc, pointer p);
  int (*is_vector)(pointer p);
  int (*list_length)(scheme *sc, pointer vec);
  long (*vector_length)(pointer vec);
  void (*fill_vector)(pointer vec, pointer elem);
  pointer (*vector_elem)(pointer vec, int ielem);
  pointer (*set_vector_elem)(pointer vec, int ielem, pointer newel);
  int (*is_port)(pointer p);

  int (*is_pair)(pointer p);
  pointer (*pair_car)(pointer p);
  pointer (*pair_cdr)(pointer p);
  pointer (*set_car)(pointer p, pointer q);
  pointer (*set_cdr)(pointer p, pointer q);

  int (*is_symbol)(pointer p);
  char *(*symname)(pointer p);

  int (*is_syntax)(pointer p);
  int (*is_proc)(pointer p);
  int (*is_foreign)(pointer p);
  char *(*syntaxname)(pointer p);
  int (*is_closure)(pointer p);
  int (*is_macro)(pointer p);
  pointer (*closure_code)(pointer p);
  pointer (*closure_env)(pointer p);

  int (*is_continuation)(pointer p);
  int (*is_promise)(pointer p);
  int (*is_environment)(pointer p);
  int (*is_immutable)(pointer p);
  void (*setimmutable)(pointer p);
  void (*load_file)(scheme *sc, FILE *fin);
  void (*load_string)(scheme *sc, const char *input);
};
#endif

#if !STANDALONE
typedef struct scheme_registerable
{
  foreign_func  f;
  const char *  name;
}
scheme_registerable;

void scheme_register_foreign_func_list(scheme * sc,
                                       scheme_registerable * list,
                                       int n);

#endif /* !STANDALONE */

#ifdef __cplusplus
}
#endif

#endif


/*
Local variables:
c-file-style: "k&r"
End:
*/

-
+ C9E5508D4522AEBF20480F5D58BFBBDF3118155CDCA7AAD2D2837D33AA5305CFA8A318DD2C8443FF5300C2BB8903466514D6051E070DA34B3F93B95EBAEADB06
bitcoin/src/shiva/scheme-knobs.h

(0 . 0)(1 . 9)
#ifndef SCHEME_KNOBS_H
#define SCHEME_KNOBS_H

#define STANDALONE       0
#define USE_INTERFACE    1
#define USE_MATH         1
#define prompt        "#>"

#endif

-
+ C74450E18AB91F7C226108E76075162D2DD9B111B10D42AF58FBFE5C2F18C71667E42CD865138DAA7339BACF158411642D62E742B208AA5133316B879081BB90
bitcoin/src/shiva/scheme-private.h

(0 . 0)(1 . 211)
/* scheme-private.h */

#ifndef _SCHEME_PRIVATE_H
#define _SCHEME_PRIVATE_H

#include "scheme.h"
/*------------------ Ugly internals -----------------------------------*/
/*------------------ Of interest only to FFI users --------------------*/

#ifdef __cplusplus
extern "C" {
#endif

enum scheme_port_kind {
  port_free=0,
  port_file=1,
  port_string=2,
  port_srfi6=4,
  port_input=16,
  port_output=32,
  port_saw_EOF=64
};

typedef struct port {
  unsigned char kind;
  union {
    struct {
      FILE *file;
      int interactive;
      int closeit;
#if SHOW_ERROR_LINE
      int curr_line;
      char *filename;
#endif
    } stdio;
    struct {
      char *start;
      char *past_the_end;
      char *curr;
    } string;
  } rep;
} port;

/* cell structure */
struct cell {
  unsigned int _flag;
  union {
    struct {
      char   *_svalue;
      int   _length;
    } _string;
    num _number;
    port *_port;
    foreign_func _ff;
    struct {
      struct cell *_car;
      struct cell *_cdr;
    } _cons;
  } _object;
};

struct scheme {
/* arrays for segments */
func_alloc malloc;
func_dealloc free;

/* return code */
int retcode;
int tracing;


#define CELL_SEGSIZE    5000  /* # of cells in one segment */
#define CELL_NSEGMENT   10    /* # of segments for cells */
char *alloc_seg[CELL_NSEGMENT];
pointer cell_seg[CELL_NSEGMENT];
int     last_cell_seg;

/* We use 4 registers. */
pointer args;            /* register for arguments of function */
pointer envir;           /* stack register for current environment */
pointer code;            /* register for current code */
pointer dump;            /* stack register for next evaluation */

int interactive_repl;    /* are we in an interactive REPL? */

struct cell _sink;
pointer sink;            /* when mem. alloc. fails */
struct cell _NIL;
pointer NIL;             /* special cell representing empty cell */
struct cell _HASHT;
pointer T;               /* special cell representing #t */
struct cell _HASHF;
pointer F;               /* special cell representing #f */
struct cell _EOF_OBJ;
pointer EOF_OBJ;         /* special cell representing end-of-file object */
pointer oblist;          /* pointer to symbol table */
pointer global_env;      /* pointer to global environment */
pointer c_nest;          /* stack for nested calls from C */

/* global pointers to special symbols */
pointer LAMBDA;               /* pointer to syntax lambda */
pointer QUOTE;           /* pointer to syntax quote */

pointer QQUOTE;               /* pointer to symbol quasiquote */
pointer UNQUOTE;         /* pointer to symbol unquote */
pointer UNQUOTESP;       /* pointer to symbol unquote-splicing */
pointer FEED_TO;         /* => */
pointer COLON_HOOK;      /* *colon-hook* */
pointer ERROR_HOOK;      /* *error-hook* */
pointer SHARP_HOOK;  /* *sharp-hook* */
pointer COMPILE_HOOK;  /* *compile-hook* */

pointer free_cell;       /* pointer to top of free cells */
long    fcells;          /* # of free cells */

pointer inport;
pointer outport;
pointer save_inport;
pointer loadport;

#define MAXFIL 64
port load_stack[MAXFIL];     /* Stack of open files for port -1 (LOADing) */
int nesting_stack[MAXFIL];
int file_i;
int nesting;

char    gc_verbose;      /* if gc_verbose is not zero, print gc status */
char    no_memory;       /* Whether mem. alloc. has failed */

#define LINESIZE 1024
char    linebuff[LINESIZE];
#define STRBUFFSIZE 256
char    strbuff[STRBUFFSIZE];

FILE *tmpfp;
int tok;
int print_flag;
pointer value;
int op;

void *ext_data;     /* For the benefit of foreign functions */
long gensym_cnt;

struct scheme_interface *vptr;
void *dump_base;    /* pointer to base of allocated dump stack */
int dump_size;      /* number of frames allocated for dump stack */
};

/* operator code */
enum scheme_opcodes {
#define _OP_DEF(A,B,C,D,E,OP) OP,
#include "opdefines.h"
  OP_MAXDEFINED
};


#define cons(sc,a,b) _cons(sc,a,b,0)
#define immutable_cons(sc,a,b) _cons(sc,a,b,1)

int is_string(pointer p);
char *string_value(pointer p);
int is_number(pointer p);
num nvalue(pointer p);
long ivalue(pointer p);
double rvalue(pointer p);
int is_integer(pointer p);
int is_real(pointer p);
int is_character(pointer p);
long charvalue(pointer p);
int is_vector(pointer p);

int is_port(pointer p);

int is_pair(pointer p);
pointer pair_car(pointer p);
pointer pair_cdr(pointer p);
pointer set_car(pointer p, pointer q);
pointer set_cdr(pointer p, pointer q);

int is_symbol(pointer p);
char *symname(pointer p);
int hasprop(pointer p);

int is_syntax(pointer p);
int is_proc(pointer p);
int is_foreign(pointer p);
char *syntaxname(pointer p);
int is_closure(pointer p);
#ifdef USE_MACRO
int is_macro(pointer p);
#endif
pointer closure_code(pointer p);
pointer closure_env(pointer p);

int is_continuation(pointer p);
int is_promise(pointer p);
int is_environment(pointer p);
int is_immutable(pointer p);
void setimmutable(pointer p);

#ifdef __cplusplus
}
#endif

#endif

/*
Local variables:
c-file-style: "k&r"
End:
*/