raw
asciilifeform_shi...    1 ;    Initialization file for TinySCHEME 1.41
asciilifeform_shi...    2 
asciilifeform_shi...    3 ; Per R5RS, up to four deep compositions should be defined
asciilifeform_shi...    4 (define (caar x) (car (car x)))
asciilifeform_shi...    5 (define (cadr x) (car (cdr x)))
asciilifeform_shi...    6 (define (cdar x) (cdr (car x)))
asciilifeform_shi...    7 (define (cddr x) (cdr (cdr x)))
asciilifeform_shi...    8 (define (caaar x) (car (car (car x))))
asciilifeform_shi...    9 (define (caadr x) (car (car (cdr x))))
asciilifeform_shi...   10 (define (cadar x) (car (cdr (car x))))
asciilifeform_shi...   11 (define (caddr x) (car (cdr (cdr x))))
asciilifeform_shi...   12 (define (cdaar x) (cdr (car (car x))))
asciilifeform_shi...   13 (define (cdadr x) (cdr (car (cdr x))))
asciilifeform_shi...   14 (define (cddar x) (cdr (cdr (car x))))
asciilifeform_shi...   15 (define (cdddr x) (cdr (cdr (cdr x))))
asciilifeform_shi...   16 (define (caaaar x) (car (car (car (car x)))))
asciilifeform_shi...   17 (define (caaadr x) (car (car (car (cdr x)))))
asciilifeform_shi...   18 (define (caadar x) (car (car (cdr (car x)))))
asciilifeform_shi...   19 (define (caaddr x) (car (car (cdr (cdr x)))))
asciilifeform_shi...   20 (define (cadaar x) (car (cdr (car (car x)))))
asciilifeform_shi...   21 (define (cadadr x) (car (cdr (car (cdr x)))))
asciilifeform_shi...   22 (define (caddar x) (car (cdr (cdr (car x)))))
asciilifeform_shi...   23 (define (cadddr x) (car (cdr (cdr (cdr x)))))
asciilifeform_shi...   24 (define (cdaaar x) (cdr (car (car (car x)))))
asciilifeform_shi...   25 (define (cdaadr x) (cdr (car (car (cdr x)))))
asciilifeform_shi...   26 (define (cdadar x) (cdr (car (cdr (car x)))))
asciilifeform_shi...   27 (define (cdaddr x) (cdr (car (cdr (cdr x)))))
asciilifeform_shi...   28 (define (cddaar x) (cdr (cdr (car (car x)))))
asciilifeform_shi...   29 (define (cddadr x) (cdr (cdr (car (cdr x)))))
asciilifeform_shi...   30 (define (cdddar x) (cdr (cdr (cdr (car x)))))
asciilifeform_shi...   31 (define (cddddr x) (cdr (cdr (cdr (cdr x)))))
asciilifeform_shi...   32 
asciilifeform_shi...   33 ;;;; Utility to ease macro creation
asciilifeform_shi...   34 (define (macro-expand form)
asciilifeform_shi...   35      ((eval (get-closure-code (eval (car form)))) form))
asciilifeform_shi...   36 
asciilifeform_shi...   37 (define (macro-expand-all form)
asciilifeform_shi...   38    (if (macro? form)
asciilifeform_shi...   39       (macro-expand-all (macro-expand form))
asciilifeform_shi...   40       form))
asciilifeform_shi...   41 
asciilifeform_shi...   42 (define *compile-hook* macro-expand-all)
asciilifeform_shi...   43 
asciilifeform_shi...   44 
asciilifeform_shi...   45 (macro (unless form)
asciilifeform_shi...   46      `(if (not ,(cadr form)) (begin ,@(cddr form))))
asciilifeform_shi...   47 
asciilifeform_shi...   48 (macro (when form)
asciilifeform_shi...   49      `(if ,(cadr form) (begin ,@(cddr form))))
asciilifeform_shi...   50 
asciilifeform_shi...   51 ; DEFINE-MACRO Contributed by Andy Gaynor
asciilifeform_shi...   52 (macro (define-macro dform)
asciilifeform_shi...   53   (if (symbol? (cadr dform))
asciilifeform_shi...   54     `(macro ,@(cdr dform))
asciilifeform_shi...   55     (let ((form (gensym)))
asciilifeform_shi...   56       `(macro (,(caadr dform) ,form)
asciilifeform_shi...   57          (apply (lambda ,(cdadr dform) ,@(cddr dform)) (cdr ,form))))))
asciilifeform_shi...   58 
asciilifeform_shi...   59 ; Utilities for math. Notice that inexact->exact is primitive,
asciilifeform_shi...   60 ; but exact->inexact is not.
asciilifeform_shi...   61 (define exact? integer?)
asciilifeform_shi...   62 (define (inexact? x) (and (real? x) (not (integer? x))))
asciilifeform_shi...   63 (define (even? n) (= (remainder n 2) 0))
asciilifeform_shi...   64 (define (odd? n) (not (= (remainder n 2) 0)))
asciilifeform_shi...   65 (define (zero? n) (= n 0))
asciilifeform_shi...   66 (define (positive? n) (> n 0))
asciilifeform_shi...   67 (define (negative? n) (< n 0))
asciilifeform_shi...   68 (define complex? number?)
asciilifeform_shi...   69 (define rational? real?)
asciilifeform_shi...   70 (define (abs n) (if (>= n 0) n (- n)))
asciilifeform_shi...   71 (define (exact->inexact n) (* n 1.0))
asciilifeform_shi...   72 (define (<> n1 n2) (not (= n1 n2)))
asciilifeform_shi...   73 
asciilifeform_shi...   74 ; min and max must return inexact if any arg is inexact; use (+ n 0.0)
asciilifeform_shi...   75 (define (max . lst)
asciilifeform_shi...   76   (foldr (lambda (a b)
asciilifeform_shi...   77            (if (> a b)
asciilifeform_shi...   78              (if (exact? b) a (+ a 0.0))
asciilifeform_shi...   79              (if (exact? a) b (+ b 0.0))))
asciilifeform_shi...   80          (car lst) (cdr lst)))
asciilifeform_shi...   81 (define (min . lst)
asciilifeform_shi...   82   (foldr (lambda (a b)
asciilifeform_shi...   83            (if (< a b)
asciilifeform_shi...   84              (if (exact? b) a (+ a 0.0))
asciilifeform_shi...   85              (if (exact? a) b (+ b 0.0))))
asciilifeform_shi...   86          (car lst) (cdr lst)))
asciilifeform_shi...   87 
asciilifeform_shi...   88 (define (succ x) (+ x 1))
asciilifeform_shi...   89 (define (pred x) (- x 1))
asciilifeform_shi...   90 (define gcd
asciilifeform_shi...   91   (lambda a
asciilifeform_shi...   92     (if (null? a)
asciilifeform_shi...   93       0
asciilifeform_shi...   94       (let ((aa (abs (car a)))
asciilifeform_shi...   95             (bb (abs (cadr a))))
asciilifeform_shi...   96          (if (= bb 0)
asciilifeform_shi...   97               aa
asciilifeform_shi...   98               (gcd bb (remainder aa bb)))))))
asciilifeform_shi...   99 (define lcm
asciilifeform_shi...  100   (lambda a
asciilifeform_shi...  101     (if (null? a)
asciilifeform_shi...  102       1
asciilifeform_shi...  103       (let ((aa (abs (car a)))
asciilifeform_shi...  104             (bb (abs (cadr a))))
asciilifeform_shi...  105          (if (or (= aa 0) (= bb 0))
asciilifeform_shi...  106              0
asciilifeform_shi...  107              (abs (* (quotient aa (gcd aa bb)) bb)))))))
asciilifeform_shi...  108 
asciilifeform_shi...  109 
asciilifeform_shi...  110 (define (string . charlist)
asciilifeform_shi...  111      (list->string charlist))
asciilifeform_shi...  112 
asciilifeform_shi...  113 (define (list->string charlist)
asciilifeform_shi...  114      (let* ((len (length charlist))
asciilifeform_shi...  115             (newstr (make-string len))
asciilifeform_shi...  116             (fill-string!
asciilifeform_shi...  117                (lambda (str i len charlist)
asciilifeform_shi...  118                     (if (= i len)
asciilifeform_shi...  119                          str
asciilifeform_shi...  120                          (begin (string-set! str i (car charlist))
asciilifeform_shi...  121                          (fill-string! str (+ i 1) len (cdr charlist)))))))
asciilifeform_shi...  122           (fill-string! newstr 0 len charlist)))
asciilifeform_shi...  123 
asciilifeform_shi...  124 (define (string-fill! s e)
asciilifeform_shi...  125      (let ((n (string-length s)))
asciilifeform_shi...  126           (let loop ((i 0))
asciilifeform_shi...  127                (if (= i n)
asciilifeform_shi...  128                     s
asciilifeform_shi...  129                     (begin (string-set! s i e) (loop (succ i)))))))
asciilifeform_shi...  130 
asciilifeform_shi...  131 (define (string->list s)
asciilifeform_shi...  132      (let loop ((n (pred (string-length s))) (l '()))
asciilifeform_shi...  133           (if (= n -1)
asciilifeform_shi...  134                l
asciilifeform_shi...  135                (loop (pred n) (cons (string-ref s n) l)))))
asciilifeform_shi...  136 
asciilifeform_shi...  137 (define (string-copy str)
asciilifeform_shi...  138      (string-append str))
asciilifeform_shi...  139 
asciilifeform_shi...  140 (define (string->anyatom str pred)
asciilifeform_shi...  141      (let* ((a (string->atom str)))
asciilifeform_shi...  142        (if (pred a) a
asciilifeform_shi...  143          (error "string->xxx: not a xxx" a))))
asciilifeform_shi...  144 
asciilifeform_shi...  145 (define (string->number str . base)
asciilifeform_shi...  146     (let ((n (string->atom str (if (null? base) 10 (car base)))))
asciilifeform_shi...  147         (if (number? n) n #f)))
asciilifeform_shi...  148 
asciilifeform_shi...  149 (define (anyatom->string n pred)
asciilifeform_shi...  150   (if (pred n)
asciilifeform_shi...  151       (atom->string n)
asciilifeform_shi...  152       (error "xxx->string: not a xxx" n)))
asciilifeform_shi...  153 
asciilifeform_shi...  154 (define (number->string n . base)
asciilifeform_shi...  155     (atom->string n (if (null? base) 10 (car base))))
asciilifeform_shi...  156 
asciilifeform_shi...  157 
asciilifeform_shi...  158 (define (char-cmp? cmp a b)
asciilifeform_shi...  159      (cmp (char->integer a) (char->integer b)))
asciilifeform_shi...  160 (define (char-ci-cmp? cmp a b)
asciilifeform_shi...  161      (cmp (char->integer (char-downcase a)) (char->integer (char-downcase b))))
asciilifeform_shi...  162 
asciilifeform_shi...  163 (define (char=? a b) (char-cmp? = a b))
asciilifeform_shi...  164 (define (char<? a b) (char-cmp? < a b))
asciilifeform_shi...  165 (define (char>? a b) (char-cmp? > a b))
asciilifeform_shi...  166 (define (char<=? a b) (char-cmp? <= a b))
asciilifeform_shi...  167 (define (char>=? a b) (char-cmp? >= a b))
asciilifeform_shi...  168 
asciilifeform_shi...  169 (define (char-ci=? a b) (char-ci-cmp? = a b))
asciilifeform_shi...  170 (define (char-ci<? a b) (char-ci-cmp? < a b))
asciilifeform_shi...  171 (define (char-ci>? a b) (char-ci-cmp? > a b))
asciilifeform_shi...  172 (define (char-ci<=? a b) (char-ci-cmp? <= a b))
asciilifeform_shi...  173 (define (char-ci>=? a b) (char-ci-cmp? >= a b))
asciilifeform_shi...  174 
asciilifeform_shi...  175 ; Note the trick of returning (cmp x y)
asciilifeform_shi...  176 (define (string-cmp? chcmp cmp a b)
asciilifeform_shi...  177      (let ((na (string-length a)) (nb (string-length b)))
asciilifeform_shi...  178           (let loop ((i 0))
asciilifeform_shi...  179                (cond
asciilifeform_shi...  180                     ((= i na)
asciilifeform_shi...  181                          (if (= i nb) (cmp 0 0) (cmp 0 1)))
asciilifeform_shi...  182                     ((= i nb)
asciilifeform_shi...  183                          (cmp 1 0))
asciilifeform_shi...  184                     ((chcmp = (string-ref a i) (string-ref b i))
asciilifeform_shi...  185                          (loop (succ i)))
asciilifeform_shi...  186                     (else
asciilifeform_shi...  187                          (chcmp cmp (string-ref a i) (string-ref b i)))))))
asciilifeform_shi...  188 
asciilifeform_shi...  189 
asciilifeform_shi...  190 (define (string=? a b) (string-cmp? char-cmp? = a b))
asciilifeform_shi...  191 (define (string<? a b) (string-cmp? char-cmp? < a b))
asciilifeform_shi...  192 (define (string>? a b) (string-cmp? char-cmp? > a b))
asciilifeform_shi...  193 (define (string<=? a b) (string-cmp? char-cmp? <= a b))
asciilifeform_shi...  194 (define (string>=? a b) (string-cmp? char-cmp? >= a b))
asciilifeform_shi...  195 
asciilifeform_shi...  196 (define (string-ci=? a b) (string-cmp? char-ci-cmp? = a b))
asciilifeform_shi...  197 (define (string-ci<? a b) (string-cmp? char-ci-cmp? < a b))
asciilifeform_shi...  198 (define (string-ci>? a b) (string-cmp? char-ci-cmp? > a b))
asciilifeform_shi...  199 (define (string-ci<=? a b) (string-cmp? char-ci-cmp? <= a b))
asciilifeform_shi...  200 (define (string-ci>=? a b) (string-cmp? char-ci-cmp? >= a b))
asciilifeform_shi...  201 
asciilifeform_shi...  202 (define (list . x) x)
asciilifeform_shi...  203 
asciilifeform_shi...  204 (define (foldr f x lst)
asciilifeform_shi...  205      (if (null? lst)
asciilifeform_shi...  206           x
asciilifeform_shi...  207           (foldr f (f x (car lst)) (cdr lst))))
asciilifeform_shi...  208 
asciilifeform_shi...  209 (define (unzip1-with-cdr . lists)
asciilifeform_shi...  210   (unzip1-with-cdr-iterative lists '() '()))
asciilifeform_shi...  211 
asciilifeform_shi...  212 (define (unzip1-with-cdr-iterative lists cars cdrs)
asciilifeform_shi...  213   (if (null? lists)
asciilifeform_shi...  214       (cons cars cdrs)
asciilifeform_shi...  215       (let ((car1 (caar lists))
asciilifeform_shi...  216             (cdr1 (cdar lists)))
asciilifeform_shi...  217         (unzip1-with-cdr-iterative
asciilifeform_shi...  218           (cdr lists)
asciilifeform_shi...  219           (append cars (list car1))
asciilifeform_shi...  220           (append cdrs (list cdr1))))))
asciilifeform_shi...  221 
asciilifeform_shi...  222 (define (map proc . lists)
asciilifeform_shi...  223   (if (null? lists)
asciilifeform_shi...  224       (apply proc)
asciilifeform_shi...  225       (if (null? (car lists))
asciilifeform_shi...  226         '()
asciilifeform_shi...  227         (let* ((unz (apply unzip1-with-cdr lists))
asciilifeform_shi...  228                (cars (car unz))
asciilifeform_shi...  229                (cdrs (cdr unz)))
asciilifeform_shi...  230           (cons (apply proc cars) (apply map (cons proc cdrs)))))))
asciilifeform_shi...  231 
asciilifeform_shi...  232 (define (for-each proc . lists)
asciilifeform_shi...  233   (if (null? lists)
asciilifeform_shi...  234       (apply proc)
asciilifeform_shi...  235       (if (null? (car lists))
asciilifeform_shi...  236         #t
asciilifeform_shi...  237         (let* ((unz (apply unzip1-with-cdr lists))
asciilifeform_shi...  238                (cars (car unz))
asciilifeform_shi...  239                (cdrs (cdr unz)))
asciilifeform_shi...  240           (apply proc cars) (apply map (cons proc cdrs))))))
asciilifeform_shi...  241 
asciilifeform_shi...  242 (define (list-tail x k)
asciilifeform_shi...  243     (if (zero? k)
asciilifeform_shi...  244         x
asciilifeform_shi...  245         (list-tail (cdr x) (- k 1))))
asciilifeform_shi...  246 
asciilifeform_shi...  247 (define (list-ref x k)
asciilifeform_shi...  248     (car (list-tail x k)))
asciilifeform_shi...  249 
asciilifeform_shi...  250 (define (last-pair x)
asciilifeform_shi...  251     (if (pair? (cdr x))
asciilifeform_shi...  252         (last-pair (cdr x))
asciilifeform_shi...  253         x))
asciilifeform_shi...  254 
asciilifeform_shi...  255 (define (head stream) (car stream))
asciilifeform_shi...  256 
asciilifeform_shi...  257 (define (tail stream) (force (cdr stream)))
asciilifeform_shi...  258 
asciilifeform_shi...  259 (define (vector-equal? x y)
asciilifeform_shi...  260      (and (vector? x) (vector? y) (= (vector-length x) (vector-length y))
asciilifeform_shi...  261           (let ((n (vector-length x)))
asciilifeform_shi...  262                (let loop ((i 0))
asciilifeform_shi...  263                     (if (= i n)
asciilifeform_shi...  264                          #t
asciilifeform_shi...  265                          (and (equal? (vector-ref x i) (vector-ref y i))
asciilifeform_shi...  266                               (loop (succ i))))))))
asciilifeform_shi...  267 
asciilifeform_shi...  268 (define (list->vector x)
asciilifeform_shi...  269      (apply vector x))
asciilifeform_shi...  270 
asciilifeform_shi...  271 (define (vector-fill! v e)
asciilifeform_shi...  272      (let ((n (vector-length v)))
asciilifeform_shi...  273           (let loop ((i 0))
asciilifeform_shi...  274                (if (= i n)
asciilifeform_shi...  275                     v
asciilifeform_shi...  276                     (begin (vector-set! v i e) (loop (succ i)))))))
asciilifeform_shi...  277 
asciilifeform_shi...  278 (define (vector->list v)
asciilifeform_shi...  279      (let loop ((n (pred (vector-length v))) (l '()))
asciilifeform_shi...  280           (if (= n -1)
asciilifeform_shi...  281                l
asciilifeform_shi...  282                (loop (pred n) (cons (vector-ref v n) l)))))
asciilifeform_shi...  283 
asciilifeform_shi...  284 ;; The following quasiquote macro is due to Eric S. Tiedemann.
asciilifeform_shi...  285 ;;   Copyright 1988 by Eric S. Tiedemann; all rights reserved.
asciilifeform_shi...  286 ;;
asciilifeform_shi...  287 ;; Subsequently modified to handle vectors: D. Souflis
asciilifeform_shi...  288 
asciilifeform_shi...  289 (macro
asciilifeform_shi...  290  quasiquote
asciilifeform_shi...  291  (lambda (l)
asciilifeform_shi...  292    (define (mcons f l r)
asciilifeform_shi...  293      (if (and (pair? r)
asciilifeform_shi...  294               (eq? (car r) 'quote)
asciilifeform_shi...  295               (eq? (car (cdr r)) (cdr f))
asciilifeform_shi...  296               (pair? l)
asciilifeform_shi...  297               (eq? (car l) 'quote)
asciilifeform_shi...  298               (eq? (car (cdr l)) (car f)))
asciilifeform_shi...  299          (if (or (procedure? f) (number? f) (string? f))
asciilifeform_shi...  300                f
asciilifeform_shi...  301                (list 'quote f))
asciilifeform_shi...  302          (if (eqv? l vector)
asciilifeform_shi...  303                (apply l (eval r))
asciilifeform_shi...  304                (list 'cons l r)
asciilifeform_shi...  305                )))
asciilifeform_shi...  306    (define (mappend f l r)
asciilifeform_shi...  307      (if (or (null? (cdr f))
asciilifeform_shi...  308              (and (pair? r)
asciilifeform_shi...  309                   (eq? (car r) 'quote)
asciilifeform_shi...  310                   (eq? (car (cdr r)) '())))
asciilifeform_shi...  311          l
asciilifeform_shi...  312          (list 'append l r)))
asciilifeform_shi...  313    (define (foo level form)
asciilifeform_shi...  314      (cond ((not (pair? form))
asciilifeform_shi...  315                (if (or (procedure? form) (number? form) (string? form))
asciilifeform_shi...  316                     form
asciilifeform_shi...  317                     (list 'quote form))
asciilifeform_shi...  318                )
asciilifeform_shi...  319            ((eq? 'quasiquote (car form))
asciilifeform_shi...  320             (mcons form ''quasiquote (foo (+ level 1) (cdr form))))
asciilifeform_shi...  321            (#t (if (zero? level)
asciilifeform_shi...  322                    (cond ((eq? (car form) 'unquote) (car (cdr form)))
asciilifeform_shi...  323                          ((eq? (car form) 'unquote-splicing)
asciilifeform_shi...  324                           (error "Unquote-splicing wasn't in a list:"
asciilifeform_shi...  325                                  form))
asciilifeform_shi...  326                          ((and (pair? (car form))
asciilifeform_shi...  327                                (eq? (car (car form)) 'unquote-splicing))
asciilifeform_shi...  328                           (mappend form (car (cdr (car form)))
asciilifeform_shi...  329                                    (foo level (cdr form))))
asciilifeform_shi...  330                          (#t (mcons form (foo level (car form))
asciilifeform_shi...  331                                          (foo level (cdr form)))))
asciilifeform_shi...  332                    (cond ((eq? (car form) 'unquote)
asciilifeform_shi...  333                           (mcons form ''unquote (foo (- level 1)
asciilifeform_shi...  334                                                      (cdr form))))
asciilifeform_shi...  335                          ((eq? (car form) 'unquote-splicing)
asciilifeform_shi...  336                           (mcons form ''unquote-splicing
asciilifeform_shi...  337                                       (foo (- level 1) (cdr form))))
asciilifeform_shi...  338                          (#t (mcons form (foo level (car form))
asciilifeform_shi...  339                                          (foo level (cdr form)))))))))
asciilifeform_shi...  340    (foo 0 (car (cdr l)))))
asciilifeform_shi...  341 
asciilifeform_shi...  342 ;;;;;Helper for the dynamic-wind definition.  By Tom Breton (Tehom)
asciilifeform_shi...  343 (define (shared-tail x y)
asciilifeform_shi...  344    (let ((len-x (length x))
asciilifeform_shi...  345          (len-y (length y)))
asciilifeform_shi...  346       (define (shared-tail-helper x y)
asciilifeform_shi...  347          (if
asciilifeform_shi...  348             (eq? x y)
asciilifeform_shi...  349             x
asciilifeform_shi...  350             (shared-tail-helper (cdr x) (cdr y))))
asciilifeform_shi...  351 
asciilifeform_shi...  352       (cond
asciilifeform_shi...  353          ((> len-x len-y)
asciilifeform_shi...  354             (shared-tail-helper
asciilifeform_shi...  355                (list-tail x (- len-x len-y))
asciilifeform_shi...  356                y))
asciilifeform_shi...  357          ((< len-x len-y)
asciilifeform_shi...  358             (shared-tail-helper
asciilifeform_shi...  359                x
asciilifeform_shi...  360                (list-tail y (- len-y len-x))))
asciilifeform_shi...  361          (#t (shared-tail-helper x y)))))
asciilifeform_shi...  362 
asciilifeform_shi...  363 ;;;;;Dynamic-wind by Tom Breton (Tehom)
asciilifeform_shi...  364 
asciilifeform_shi...  365 ;;Guarded because we must only eval this once, because doing so
asciilifeform_shi...  366 ;;redefines call/cc in terms of old call/cc
asciilifeform_shi...  367 (unless (defined? 'dynamic-wind)
asciilifeform_shi...  368    (let
asciilifeform_shi...  369       ;;These functions are defined in the context of a private list of
asciilifeform_shi...  370       ;;pairs of before/after procs.
asciilifeform_shi...  371       (  (*active-windings* '())
asciilifeform_shi...  372          ;;We'll define some functions into the larger environment, so
asciilifeform_shi...  373          ;;we need to know it.
asciilifeform_shi...  374          (outer-env (current-environment)))
asciilifeform_shi...  375 
asciilifeform_shi...  376       ;;Poor-man's structure operations
asciilifeform_shi...  377       (define before-func car)
asciilifeform_shi...  378       (define after-func  cdr)
asciilifeform_shi...  379       (define make-winding cons)
asciilifeform_shi...  380 
asciilifeform_shi...  381       ;;Manage active windings
asciilifeform_shi...  382       (define (activate-winding! new)
asciilifeform_shi...  383          ((before-func new))
asciilifeform_shi...  384          (set! *active-windings* (cons new *active-windings*)))
asciilifeform_shi...  385       (define (deactivate-top-winding!)
asciilifeform_shi...  386          (let ((old-top (car *active-windings*)))
asciilifeform_shi...  387             ;;Remove it from the list first so it's not active during its
asciilifeform_shi...  388             ;;own exit.
asciilifeform_shi...  389             (set! *active-windings* (cdr *active-windings*))
asciilifeform_shi...  390             ((after-func old-top))))
asciilifeform_shi...  391 
asciilifeform_shi...  392       (define (set-active-windings! new-ws)
asciilifeform_shi...  393          (unless (eq? new-ws *active-windings*)
asciilifeform_shi...  394             (let ((shared (shared-tail new-ws *active-windings*)))
asciilifeform_shi...  395 
asciilifeform_shi...  396                ;;Define the looping functions.
asciilifeform_shi...  397                ;;Exit the old list.  Do deeper ones last.  Don't do
asciilifeform_shi...  398                ;;any shared ones.
asciilifeform_shi...  399                (define (pop-many)
asciilifeform_shi...  400                   (unless (eq? *active-windings* shared)
asciilifeform_shi...  401                      (deactivate-top-winding!)
asciilifeform_shi...  402                      (pop-many)))
asciilifeform_shi...  403                ;;Enter the new list.  Do deeper ones first so that the
asciilifeform_shi...  404                ;;deeper windings will already be active.  Don't do any
asciilifeform_shi...  405                ;;shared ones.
asciilifeform_shi...  406                (define (push-many new-ws)
asciilifeform_shi...  407                   (unless (eq? new-ws shared)
asciilifeform_shi...  408                      (push-many (cdr new-ws))
asciilifeform_shi...  409                      (activate-winding! (car new-ws))))
asciilifeform_shi...  410 
asciilifeform_shi...  411                ;;Do it.
asciilifeform_shi...  412                (pop-many)
asciilifeform_shi...  413                (push-many new-ws))))
asciilifeform_shi...  414 
asciilifeform_shi...  415       ;;The definitions themselves.
asciilifeform_shi...  416       (eval
asciilifeform_shi...  417          `(define call-with-current-continuation
asciilifeform_shi...  418              ;;It internally uses the built-in call/cc, so capture it.
asciilifeform_shi...  419              ,(let ((old-c/cc call-with-current-continuation))
asciilifeform_shi...  420                  (lambda (func)
asciilifeform_shi...  421                     ;;Use old call/cc to get the continuation.
asciilifeform_shi...  422                     (old-c/cc
asciilifeform_shi...  423                        (lambda (continuation)
asciilifeform_shi...  424                           ;;Call func with not the continuation itself
asciilifeform_shi...  425                           ;;but a procedure that adjusts the active
asciilifeform_shi...  426                           ;;windings to what they were when we made
asciilifeform_shi...  427                           ;;this, and only then calls the
asciilifeform_shi...  428                           ;;continuation.
asciilifeform_shi...  429                           (func
asciilifeform_shi...  430                              (let ((current-ws *active-windings*))
asciilifeform_shi...  431                                 (lambda (x)
asciilifeform_shi...  432                                    (set-active-windings! current-ws)
asciilifeform_shi...  433                                    (continuation x)))))))))
asciilifeform_shi...  434          outer-env)
asciilifeform_shi...  435       ;;We can't just say "define (dynamic-wind before thunk after)"
asciilifeform_shi...  436       ;;because the lambda it's defined to lives in this environment,
asciilifeform_shi...  437       ;;not in the global environment.
asciilifeform_shi...  438       (eval
asciilifeform_shi...  439          `(define dynamic-wind
asciilifeform_shi...  440              ,(lambda (before thunk after)
asciilifeform_shi...  441                  ;;Make a new winding
asciilifeform_shi...  442                  (activate-winding! (make-winding before after))
asciilifeform_shi...  443                  (let ((result (thunk)))
asciilifeform_shi...  444                     ;;Get rid of the new winding.
asciilifeform_shi...  445                     (deactivate-top-winding!)
asciilifeform_shi...  446                     ;;The return value is that of thunk.
asciilifeform_shi...  447                     result)))
asciilifeform_shi...  448          outer-env)))
asciilifeform_shi...  449 
asciilifeform_shi...  450 (define call/cc call-with-current-continuation)
asciilifeform_shi...  451 
asciilifeform_shi...  452 
asciilifeform_shi...  453 ;;;;; atom? and equal? written by a.k
asciilifeform_shi...  454 
asciilifeform_shi...  455 ;;;; atom?
asciilifeform_shi...  456 (define (atom? x)
asciilifeform_shi...  457   (not (pair? x)))
asciilifeform_shi...  458 
asciilifeform_shi...  459 ;;;;    equal?
asciilifeform_shi...  460 (define (equal? x y)
asciilifeform_shi...  461      (cond
asciilifeform_shi...  462           ((pair? x)
asciilifeform_shi...  463                (and (pair? y)
asciilifeform_shi...  464                     (equal? (car x) (car y))
asciilifeform_shi...  465                     (equal? (cdr x) (cdr y))))
asciilifeform_shi...  466           ((vector? x)
asciilifeform_shi...  467                (and (vector? y) (vector-equal? x y)))
asciilifeform_shi...  468           ((string? x)
asciilifeform_shi...  469                (and (string? y) (string=? x y)))
asciilifeform_shi...  470           (else (eqv? x y))))
asciilifeform_shi...  471 
asciilifeform_shi...  472 ;;;; (do ((var init inc) ...) (endtest result ...) body ...)
asciilifeform_shi...  473 ;;
asciilifeform_shi...  474 (macro do
asciilifeform_shi...  475   (lambda (do-macro)
asciilifeform_shi...  476     (apply (lambda (do vars endtest . body)
asciilifeform_shi...  477              (let ((do-loop (gensym)))
asciilifeform_shi...  478                `(letrec ((,do-loop
asciilifeform_shi...  479                            (lambda ,(map (lambda (x)
asciilifeform_shi...  480                                            (if (pair? x) (car x) x))
asciilifeform_shi...  481                                       `,vars)
asciilifeform_shi...  482                              (if ,(car endtest)
asciilifeform_shi...  483                                (begin ,@(cdr endtest))
asciilifeform_shi...  484                                (begin
asciilifeform_shi...  485                                  ,@body
asciilifeform_shi...  486                                  (,do-loop
asciilifeform_shi...  487                                    ,@(map (lambda (x)
asciilifeform_shi...  488                                             (cond
asciilifeform_shi...  489                                               ((not (pair? x)) x)
asciilifeform_shi...  490                                               ((< (length x) 3) (car x))
asciilifeform_shi...  491                                               (else (car (cdr (cdr x))))))
asciilifeform_shi...  492                                        `,vars)))))))
asciilifeform_shi...  493                   (,do-loop
asciilifeform_shi...  494                     ,@(map (lambda (x)
asciilifeform_shi...  495                              (if (and (pair? x) (cdr x))
asciilifeform_shi...  496                                (car (cdr x))
asciilifeform_shi...  497                                '()))
asciilifeform_shi...  498                         `,vars)))))
asciilifeform_shi...  499       do-macro)))
asciilifeform_shi...  500 
asciilifeform_shi...  501 ;;;; generic-member
asciilifeform_shi...  502 (define (generic-member cmp obj lst)
asciilifeform_shi...  503   (cond
asciilifeform_shi...  504     ((null? lst) #f)
asciilifeform_shi...  505     ((cmp obj (car lst)) lst)
asciilifeform_shi...  506     (else (generic-member cmp obj (cdr lst)))))
asciilifeform_shi...  507 
asciilifeform_shi...  508 (define (memq obj lst)
asciilifeform_shi...  509      (generic-member eq? obj lst))
asciilifeform_shi...  510 (define (memv obj lst)
asciilifeform_shi...  511      (generic-member eqv? obj lst))
asciilifeform_shi...  512 (define (member obj lst)
asciilifeform_shi...  513      (generic-member equal? obj lst))
asciilifeform_shi...  514 
asciilifeform_shi...  515 ;;;; generic-assoc
asciilifeform_shi...  516 (define (generic-assoc cmp obj alst)
asciilifeform_shi...  517      (cond
asciilifeform_shi...  518           ((null? alst) #f)
asciilifeform_shi...  519           ((cmp obj (caar alst)) (car alst))
asciilifeform_shi...  520           (else (generic-assoc cmp obj (cdr alst)))))
asciilifeform_shi...  521 
asciilifeform_shi...  522 (define (assq obj alst)
asciilifeform_shi...  523      (generic-assoc eq? obj alst))
asciilifeform_shi...  524 (define (assv obj alst)
asciilifeform_shi...  525      (generic-assoc eqv? obj alst))
asciilifeform_shi...  526 (define (assoc obj alst)
asciilifeform_shi...  527      (generic-assoc equal? obj alst))
asciilifeform_shi...  528 
asciilifeform_shi...  529 (define (acons x y z) (cons (cons x y) z))
asciilifeform_shi...  530 
asciilifeform_shi...  531 ;;;; Handy for imperative programs
asciilifeform_shi...  532 ;;;; Used as: (define-with-return (foo x y) .... (return z) ...)
asciilifeform_shi...  533 (macro (define-with-return form)
asciilifeform_shi...  534      `(define ,(cadr form)
asciilifeform_shi...  535           (call/cc (lambda (return) ,@(cddr form)))))
asciilifeform_shi...  536 
asciilifeform_shi...  537 ;;;; Simple exception handling
asciilifeform_shi...  538 ;
asciilifeform_shi...  539 ;    Exceptions are caught as follows:
asciilifeform_shi...  540 ;
asciilifeform_shi...  541 ;         (catch (do-something to-recover and-return meaningful-value)
asciilifeform_shi...  542 ;              (if-something goes-wrong)
asciilifeform_shi...  543 ;              (with-these calls))
asciilifeform_shi...  544 ;
asciilifeform_shi...  545 ;    "Catch" establishes a scope spanning multiple call-frames
asciilifeform_shi...  546 ;    until another "catch" is encountered.
asciilifeform_shi...  547 ;
asciilifeform_shi...  548 ;    Exceptions are thrown with:
asciilifeform_shi...  549 ;
asciilifeform_shi...  550 ;         (throw "message")
asciilifeform_shi...  551 ;
asciilifeform_shi...  552 ;    If used outside a (catch ...), reverts to (error "message)
asciilifeform_shi...  553 
asciilifeform_shi...  554 (define *handlers* (list))
asciilifeform_shi...  555 
asciilifeform_shi...  556 (define (push-handler proc)
asciilifeform_shi...  557      (set! *handlers* (cons proc *handlers*)))
asciilifeform_shi...  558 
asciilifeform_shi...  559 (define (pop-handler)
asciilifeform_shi...  560      (let ((h (car *handlers*)))
asciilifeform_shi...  561           (set! *handlers* (cdr *handlers*))
asciilifeform_shi...  562           h))
asciilifeform_shi...  563 
asciilifeform_shi...  564 (define (more-handlers?)
asciilifeform_shi...  565      (pair? *handlers*))
asciilifeform_shi...  566 
asciilifeform_shi...  567 (define (throw . x)
asciilifeform_shi...  568      (if (more-handlers?)
asciilifeform_shi...  569           (apply (pop-handler))
asciilifeform_shi...  570           (apply error x)))
asciilifeform_shi...  571 
asciilifeform_shi...  572 (macro (catch form)
asciilifeform_shi...  573      (let ((label (gensym)))
asciilifeform_shi...  574           `(call/cc (lambda (exit)
asciilifeform_shi...  575                (push-handler (lambda () (exit ,(cadr form))))
asciilifeform_shi...  576                (let ((,label (begin ,@(cddr form))))
asciilifeform_shi...  577                     (pop-handler)
asciilifeform_shi...  578                     ,label)))))
asciilifeform_shi...  579 
asciilifeform_shi...  580 (define *error-hook* throw)
asciilifeform_shi...  581 
asciilifeform_shi...  582 
asciilifeform_shi...  583 ;;;;; Definition of MAKE-ENVIRONMENT, to be used with two-argument EVAL
asciilifeform_shi...  584 
asciilifeform_shi...  585 (macro (make-environment form)
asciilifeform_shi...  586      `(apply (lambda ()
asciilifeform_shi...  587                ,@(cdr form)
asciilifeform_shi...  588                (current-environment))))
asciilifeform_shi...  589 
asciilifeform_shi...  590 (define-macro (eval-polymorphic x . envl)
asciilifeform_shi...  591   (display envl)
asciilifeform_shi...  592   (let* ((env (if (null? envl) (current-environment) (eval (car envl))))
asciilifeform_shi...  593          (xval (eval x env)))
asciilifeform_shi...  594     (if (closure? xval)
asciilifeform_shi...  595       (make-closure (get-closure-code xval) env)
asciilifeform_shi...  596       xval)))
asciilifeform_shi...  597 
asciilifeform_shi...  598 ; Redefine this if you install another package infrastructure
asciilifeform_shi...  599 ; Also redefine 'package'
asciilifeform_shi...  600 (define *colon-hook* eval)
asciilifeform_shi...  601 
asciilifeform_shi...  602 ;;;;; I/O
asciilifeform_shi...  603 
asciilifeform_shi...  604 (define (input-output-port? p)
asciilifeform_shi...  605      (and (input-port? p) (output-port? p)))
asciilifeform_shi...  606 
asciilifeform_shi...  607 (define (close-port p)
asciilifeform_shi...  608      (cond
asciilifeform_shi...  609           ((input-output-port? p) (close-input-port (close-output-port p)))
asciilifeform_shi...  610           ((input-port? p) (close-input-port p))
asciilifeform_shi...  611           ((output-port? p) (close-output-port p))
asciilifeform_shi...  612           (else (throw "Not a port" p))))
asciilifeform_shi...  613 
asciilifeform_shi...  614 (define (call-with-input-file s p)
asciilifeform_shi...  615      (let ((inport (open-input-file s)))
asciilifeform_shi...  616           (if (eq? inport #f)
asciilifeform_shi...  617                #f
asciilifeform_shi...  618                (let ((res (p inport)))
asciilifeform_shi...  619                     (close-input-port inport)
asciilifeform_shi...  620                     res))))
asciilifeform_shi...  621 
asciilifeform_shi...  622 (define (call-with-output-file s p)
asciilifeform_shi...  623      (let ((outport (open-output-file s)))
asciilifeform_shi...  624           (if (eq? outport #f)
asciilifeform_shi...  625                #f
asciilifeform_shi...  626                (let ((res (p outport)))
asciilifeform_shi...  627                     (close-output-port outport)
asciilifeform_shi...  628                     res))))
asciilifeform_shi...  629 
asciilifeform_shi...  630 (define (with-input-from-file s p)
asciilifeform_shi...  631      (let ((inport (open-input-file s)))
asciilifeform_shi...  632           (if (eq? inport #f)
asciilifeform_shi...  633                #f
asciilifeform_shi...  634                (let ((prev-inport (current-input-port)))
asciilifeform_shi...  635                     (set-input-port inport)
asciilifeform_shi...  636                     (let ((res (p)))
asciilifeform_shi...  637                          (close-input-port inport)
asciilifeform_shi...  638                          (set-input-port prev-inport)
asciilifeform_shi...  639                          res)))))
asciilifeform_shi...  640 
asciilifeform_shi...  641 (define (with-output-to-file s p)
asciilifeform_shi...  642      (let ((outport (open-output-file s)))
asciilifeform_shi...  643           (if (eq? outport #f)
asciilifeform_shi...  644                #f
asciilifeform_shi...  645                (let ((prev-outport (current-output-port)))
asciilifeform_shi...  646                     (set-output-port outport)
asciilifeform_shi...  647                     (let ((res (p)))
asciilifeform_shi...  648                          (close-output-port outport)
asciilifeform_shi...  649                          (set-output-port prev-outport)
asciilifeform_shi...  650                          res)))))
asciilifeform_shi...  651 
asciilifeform_shi...  652 (define (with-input-output-from-to-files si so p)
asciilifeform_shi...  653      (let ((inport (open-input-file si))
asciilifeform_shi...  654            (outport (open-input-file so)))
asciilifeform_shi...  655           (if (not (and inport outport))
asciilifeform_shi...  656                (begin
asciilifeform_shi...  657                     (close-input-port inport)
asciilifeform_shi...  658                     (close-output-port outport)
asciilifeform_shi...  659                     #f)
asciilifeform_shi...  660                (let ((prev-inport (current-input-port))
asciilifeform_shi...  661                      (prev-outport (current-output-port)))
asciilifeform_shi...  662                     (set-input-port inport)
asciilifeform_shi...  663                     (set-output-port outport)
asciilifeform_shi...  664                     (let ((res (p)))
asciilifeform_shi...  665                          (close-input-port inport)
asciilifeform_shi...  666                          (close-output-port outport)
asciilifeform_shi...  667                          (set-input-port prev-inport)
asciilifeform_shi...  668                          (set-output-port prev-outport)
asciilifeform_shi...  669                          res)))))
asciilifeform_shi...  670 
asciilifeform_shi...  671 ; Random number generator (maximum cycle)
asciilifeform_shi...  672 (define *seed* 1)
asciilifeform_shi...  673 (define (random-next)
asciilifeform_shi...  674      (let* ((a 16807) (m 2147483647) (q (quotient m a)) (r (modulo m a)))
asciilifeform_shi...  675           (set! *seed*
asciilifeform_shi...  676                (-   (* a (- *seed*
asciilifeform_shi...  677                          (* (quotient *seed* q) q)))
asciilifeform_shi...  678                     (* (quotient *seed* q) r)))
asciilifeform_shi...  679           (if (< *seed* 0) (set! *seed* (+ *seed* m)))
asciilifeform_shi...  680           *seed*))
asciilifeform_shi...  681 ;; SRFI-0
asciilifeform_shi...  682 ;; COND-EXPAND
asciilifeform_shi...  683 ;; Implemented as a macro
asciilifeform_shi...  684 (define *features* '(srfi-0))
asciilifeform_shi...  685 
asciilifeform_shi...  686 (define-macro (cond-expand . cond-action-list)
asciilifeform_shi...  687   (cond-expand-runtime cond-action-list))
asciilifeform_shi...  688 
asciilifeform_shi...  689 (define (cond-expand-runtime cond-action-list)
asciilifeform_shi...  690   (if (null? cond-action-list)
asciilifeform_shi...  691       #t
asciilifeform_shi...  692       (if (cond-eval (caar cond-action-list))
asciilifeform_shi...  693           `(begin ,@(cdar cond-action-list))
asciilifeform_shi...  694           (cond-expand-runtime (cdr cond-action-list)))))
asciilifeform_shi...  695 
asciilifeform_shi...  696 (define (cond-eval-and cond-list)
asciilifeform_shi...  697   (foldr (lambda (x y) (and (cond-eval x) (cond-eval y))) #t cond-list))
asciilifeform_shi...  698 
asciilifeform_shi...  699 (define (cond-eval-or cond-list)
asciilifeform_shi...  700   (foldr (lambda (x y) (or (cond-eval x) (cond-eval y))) #f cond-list))
asciilifeform_shi...  701 
asciilifeform_shi...  702 (define (cond-eval condition)
asciilifeform_shi...  703   (cond
asciilifeform_shi...  704     ((symbol? condition)
asciilifeform_shi...  705        (if (member condition *features*) #t #f))
asciilifeform_shi...  706     ((eq? condition #t) #t)
asciilifeform_shi...  707     ((eq? condition #f) #f)
asciilifeform_shi...  708     (else (case (car condition)
asciilifeform_shi...  709             ((and) (cond-eval-and (cdr condition)))
asciilifeform_shi...  710             ((or) (cond-eval-or (cdr condition)))
asciilifeform_shi...  711             ((not) (if (not (null? (cddr condition)))
asciilifeform_shi...  712                      (error "cond-expand : 'not' takes 1 argument")
asciilifeform_shi...  713                      (not (cond-eval (cadr condition)))))
asciilifeform_shi...  714             (else (error "cond-expand : unknown operator" (car condition)))))))
asciilifeform_shi...  715 
asciilifeform_shi...  716 (gc-verbose #f)