Merge remote-tracking branch 'origin/stable-2.0'
[bpt/guile.git] / module / ice-9 / eval.scm
index e6e5f17..fdf16c8 100644 (file)
@@ -1,7 +1,6 @@
 ;;; -*- mode: scheme; coding: utf-8; -*-
 
-;;;; Copyright (C) 2009, 2010
-;;;; Free Software Foundation, Inc.
+;;;; Copyright (C) 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.
 ;;;;
 ;;;; This library is free software; you can redistribute it and/or
 ;;;; modify it under the terms of the GNU Lesser General Public
@@ -46,6 +45,9 @@
 (eval-when (compile)
   (define-syntax capture-env
     (syntax-rules ()
+      ((_ (exp ...))
+       (let ((env (exp ...)))
+         (capture-env env)))
       ((_ env)
        (if (null? env)
            (current-module)
@@ -62,7 +64,7 @@
       (define (make-formals n)
         (map (lambda (i)
                (datum->syntax
-                x 
+                x
                 (string->symbol
                  (string (integer->char (+ (char->integer #\a) i))))))
              (iota n)))
 ;;;       module-ref: 14468
 ;;;           define: 1259
 ;;;     toplevel-set: 328
-;;;          dynwind: 162
-;;;      with-fluids: 0
 ;;;          call/cc: 0
 ;;;       module-set: 0
 ;;;
     ;; multiple arities, as with case-lambda.
     (define (make-general-closure env body nreq rest? nopt kw inits alt)
       (define alt-proc
-        (and alt
-             (apply make-general-closure env (memoized-expression-data alt))))
-      (lambda %args
-        (let lp ((env env)
-                 (nreq* nreq)
-                 (args %args))
-          (if (> nreq* 0)
-              ;; First, bind required arguments.
-              (if (null? args)
-                  (if alt
-                      (apply alt-proc %args)
-                      (scm-error 'wrong-number-of-args
-                                 "eval" "Wrong number of arguments"
-                                 '() #f))
-                  (lp (cons (car args) env)
-                      (1- nreq*)
-                      (cdr args)))
-              ;; Move on to optional arguments.
-              (if (not kw)
-                  ;; Without keywords, bind optionals from arguments.
-                  (let lp ((env env)
-                           (nopt nopt)
-                           (args args)
-                           (inits inits))
-                    (if (zero? nopt)
-                        (if rest?
-                            (eval body (cons args env))
-                            (if (null? args)
-                                (eval body env)
-                                (if alt
-                                    (apply alt-proc %args)
-                                    (scm-error 'wrong-number-of-args
-                                               "eval" "Wrong number of arguments"
-                                               '() #f))))
-                        (if (null? args)
-                            (lp (cons (eval (car inits) env) env)
-                                (1- nopt) args (cdr inits))
-                            (lp (cons (car args) env)
-                                (1- nopt) (cdr args) (cdr inits)))))
-                  ;; With keywords, we stop binding optionals at the first
-                  ;; keyword.
-                  (let lp ((env env)
-                           (nopt* nopt)
-                           (args args)
-                           (inits inits))
-                    (if (> nopt* 0)
-                        (if (or (null? args) (keyword? (car args)))
-                            (lp (cons (eval (car inits) env) env)
-                                (1- nopt*) args (cdr inits))
-                            (lp (cons (car args) env)
-                                (1- nopt*) (cdr args) (cdr inits)))
-                        ;; Finished with optionals.
-                        (let* ((aok (car kw))
-                               (kw (cdr kw))
-                               (kw-base (+ nopt nreq (if rest? 1 0)))
-                               (imax (let lp ((imax (1- kw-base)) (kw kw))
-                                       (if (null? kw)
-                                           imax
-                                           (lp (max (cdar kw) imax)
-                                               (cdr kw)))))
-                               ;; Fill in kwargs  with "undefined" vals.
-                               (env (let lp ((i kw-base)
-                                             ;; Also, here we bind the rest
-                                             ;; arg, if any.
-                                             (env (if rest? (cons args env) env)))
-                                      (if (<= i imax)
-                                          (lp (1+ i) (cons unbound-arg env))
-                                          env))))
-                          ;; Now scan args for keywords.
-                          (let lp ((args args))
-                            (if (and (pair? args) (pair? (cdr args))
-                                     (keyword? (car args)))
-                                (let ((kw-pair (assq (car args) kw))
-                                      (v (cadr args)))
-                                  (if kw-pair
-                                      ;; Found a known keyword; set its value.
-                                      (list-set! env (- imax (cdr kw-pair)) v)
-                                      ;; Unknown keyword.
-                                      (if (not aok)
-                                          (scm-error 'keyword-argument-error
-                                                     "eval" "Unrecognized keyword"
-                                                     '() #f)))
-                                  (lp (cddr args)))
-                                (if (pair? args)
-                                    (if rest?
-                                        ;; Be lenient parsing rest args.
-                                        (lp (cdr args))
-                                        (scm-error 'keyword-argument-error
-                                                   "eval" "Invalid keyword"
-                                                   '() #f))
-                                    ;; Finished parsing keywords. Fill in
-                                    ;; uninitialized kwargs by evalling init
-                                    ;; expressions in their appropriate
-                                    ;; environment.
-                                    (let lp ((i (- imax kw-base))
-                                             (inits inits))
-                                      (if (pair? inits)
-                                          (let ((tail (list-tail env i)))
-                                            (if (eq? (car tail) unbound-arg)
-                                                (set-car! tail
-                                                          (eval (car inits)
-                                                                (cdr tail))))
-                                            (lp (1- i) (cdr inits)))
-                                          ;; Finally, eval the body.
-                                          (eval body env))))))))))))))
+        (and alt                             ; (body docstring nreq ...)
+             (let* ((body (car alt))
+                    (spec (cddr alt))
+                    (nreq (car spec))
+                    (rest (if (null? (cdr spec)) #f (cadr spec)))
+                    (tail (and (pair? (cdr spec)) (pair? (cddr spec)) (cddr spec)))
+                    (nopt (if tail (car tail) 0))
+                    (kw (and tail (cadr tail)))
+                    (inits (if tail (caddr tail) '()))
+                    (alt (and tail (cadddr tail))))
+               (make-general-closure env body nreq rest nopt kw inits alt))))
+      (define (set-procedure-arity! proc)
+        (let lp ((alt alt) (nreq nreq) (nopt nopt) (rest? rest?))
+          (if (not alt)
+              (begin
+                (set-procedure-property! proc 'arglist
+                                         (list nreq
+                                               nopt
+                                               (if kw (cdr kw) '())
+                                               (and kw (car kw))
+                                               (and rest? '_)))
+                (set-procedure-minimum-arity! proc nreq nopt rest?))
+              (let* ((spec (cddr alt))
+                     (nreq* (car spec))
+                     (rest?* (if (null? (cdr spec)) #f (cadr spec)))
+                     (tail (and (pair? (cdr spec)) (pair? (cddr spec)) (cddr spec)))
+                     (nopt* (if tail (car tail) 0))
+                     (alt* (and tail (cadddr tail))))
+                (if (or (< nreq* nreq)
+                        (and (= nreq* nreq)
+                             (if rest?
+                                 (and rest?* (> nopt* nopt))
+                                 (or rest?* (> nopt* nopt)))))
+                    (lp alt* nreq* nopt* rest?*)
+                    (lp alt* nreq nopt rest?)))))
+        proc)
+      (set-procedure-arity!
+       (lambda %args
+         (let lp ((env env)
+                  (nreq* nreq)
+                  (args %args))
+           (if (> nreq* 0)
+               ;; First, bind required arguments.
+               (if (null? args)
+                   (if alt
+                       (apply alt-proc %args)
+                       (scm-error 'wrong-number-of-args
+                                  "eval" "Wrong number of arguments"
+                                  '() #f))
+                   (lp (cons (car args) env)
+                       (1- nreq*)
+                       (cdr args)))
+               ;; Move on to optional arguments.
+               (if (not kw)
+                   ;; Without keywords, bind optionals from arguments.
+                   (let lp ((env env)
+                            (nopt nopt)
+                            (args args)
+                            (inits inits))
+                     (if (zero? nopt)
+                         (if rest?
+                             (eval body (cons args env))
+                             (if (null? args)
+                                 (eval body env)
+                                 (if alt
+                                     (apply alt-proc %args)
+                                     (scm-error 'wrong-number-of-args
+                                                "eval" "Wrong number of arguments"
+                                                '() #f))))
+                         (if (null? args)
+                             (lp (cons (eval (car inits) env) env)
+                                 (1- nopt) args (cdr inits))
+                             (lp (cons (car args) env)
+                                 (1- nopt) (cdr args) (cdr inits)))))
+                   (let lp ((env env)
+                            (nopt* nopt)
+                            (args args)
+                            (inits inits))
+                     (cond
+                      ;; With keywords, we stop binding optionals at the
+                      ;; first keyword.
+                      ((> nopt* 0)
+                       (if (or (null? args) (keyword? (car args)))
+                           (lp (cons (eval (car inits) env) env)
+                               (1- nopt*) args (cdr inits))
+                           (lp (cons (car args) env)
+                               (1- nopt*) (cdr args) (cdr inits))))
+                      ;; Finished with optionals.
+                      ((and alt (pair? args) (not (keyword? (car args)))
+                            (not rest?))
+                       ;; Too many positional args, no #:rest arg,
+                       ;; and we have an alternate.
+                       (apply alt-proc %args))
+                      (else
+                       (let* ((aok (car kw))
+                              (kw (cdr kw))
+                              (kw-base (+ nopt nreq (if rest? 1 0)))
+                              (imax (let lp ((imax (1- kw-base)) (kw kw))
+                                      (if (null? kw)
+                                          imax
+                                          (lp (max (cdar kw) imax)
+                                              (cdr kw)))))
+                              ;; Fill in kwargs  with "undefined" vals.
+                              (env (let lp ((i kw-base)
+                                            ;; Also, here we bind the rest
+                                            ;; arg, if any.
+                                            (env (if rest?
+                                                     (cons args env)
+                                                     env)))
+                                     (if (<= i imax)
+                                         (lp (1+ i) (cons unbound-arg env))
+                                         env))))
+                         ;; Now scan args for keywords.
+                         (let lp ((args args))
+                           (if (and (pair? args) (pair? (cdr args))
+                                    (keyword? (car args)))
+                               (let ((kw-pair (assq (car args) kw))
+                                     (v (cadr args)))
+                                 (if kw-pair
+                                     ;; Found a known keyword; set its value.
+                                     (list-set! env
+                                                (- imax (cdr kw-pair)) v)
+                                     ;; Unknown keyword.
+                                     (if (not aok)
+                                         (scm-error
+                                          'keyword-argument-error
+                                          "eval" "Unrecognized keyword"
+                                          '() (list (car args)))))
+                                 (lp (cddr args)))
+                               (if (pair? args)
+                                   (if rest?
+                                       ;; Be lenient parsing rest args.
+                                       (lp (cdr args))
+                                       (scm-error 'keyword-argument-error
+                                                  "eval" "Invalid keyword"
+                                                  '() (list (car args))))
+                                   ;; Finished parsing keywords. Fill in
+                                   ;; uninitialized kwargs by evalling init
+                                   ;; expressions in their appropriate
+                                   ;; environment.
+                                   (let lp ((i (- imax kw-base))
+                                            (inits inits))
+                                     (if (pair? inits)
+                                         (let ((tail (list-tail env i)))
+                                           (if (eq? (car tail) unbound-arg)
+                                               (set-car! tail
+                                                         (eval (car inits)
+                                                               (cdr tail))))
+                                           (lp (1- i) (cdr inits)))
+                                         ;; Finally, eval the body.
+                                         (eval body env))))))))))))))))
 
     ;; The "engine". EXP is a memoized expression.
     (define (eval exp env)
       (memoized-expression-case exp
         (('lexical-ref n)
-         (let lp ((n n) (env env))
-           (if (zero? n)
-               (car env)
-               (lp (1- n) (cdr env)))))
-      
+         (list-ref env n))
+        
         (('call (f nargs . args))
          (let ((proc (eval f env)))
            (call eval proc nargs args env)))
          (variable-ref
           (if (variable? var-or-sym)
               var-or-sym
-              (let lp ((env env))
-                (if (pair? env)
-                    (lp (cdr env))
-                    (memoize-variable-access! exp (capture-env env)))))))
+              (memoize-variable-access! exp
+                                        (capture-env (if (pair? env)
+                                                         (cdr (last-pair env))
+                                                         env))))))
 
         (('if (test consequent . alternate))
          (if (eval test env)
                (eval body new-env)
                (lp (cdr inits)
                    (cons (eval (car inits) env) new-env)))))
-      
-        (('lambda (body nreq . tail))
-         (if (null? tail)
-             (make-fixed-closure eval nreq body (capture-env env))
-             (if (null? (cdr tail))
-                 (make-general-closure (capture-env env) body nreq (car tail)
-                                       0 #f '() #f)
-                 (apply make-general-closure (capture-env env) body nreq tail))))
 
-        (('begin (first . rest))
-         (let lp ((first first) (rest rest))
-           (if (null? rest)
-               (eval first env)
-               (begin
-                 (eval first env)
-                 (lp (car rest) (cdr rest))))))
-      
+        (('lambda (body docstring nreq . tail))
+         (let ((proc
+                (if (null? tail)
+                    (make-fixed-closure eval nreq body (capture-env env))
+                    (if (null? (cdr tail))
+                        (make-general-closure (capture-env env) body
+                                              nreq (car tail)
+                                              0 #f '() #f)
+                        (apply make-general-closure (capture-env env)
+                               body nreq tail)))))
+           (when docstring
+             (set-procedure-property! proc 'documentation docstring))
+           proc))
+
+        (('seq (head . tail))
+         (begin
+           (eval head env)
+           (eval tail env)))
+        
         (('lexical-set! (n . x))
          (let ((val (eval x env)))
-           (let lp ((n n) (env env))
-             (if (zero? n)
-                 (set-car! env val)
-                 (lp (1- n) (cdr env))))))
+           (list-set! env n val)))
         
         (('call-with-values (producer . consumer))
          (call-with-values (eval producer env)
               (memoize-variable-access! exp #f))))
 
         (('define (name . x))
-         (define! name (eval x env)))
+         (let ((x (eval x env)))
+           (if (and (procedure? x) (not (procedure-property x 'name)))
+               (set-procedure-property! x 'name name))
+           (define! name x)
+           (if #f #f)))
       
         (('toplevel-set! (var-or-sym . x))
          (variable-set!
           (if (variable? var-or-sym)
               var-or-sym
-              (let lp ((env env))
-                (if (pair? env)
-                    (lp (cdr env))
-                    (memoize-variable-access! exp (capture-env env)))))
+              (memoize-variable-access! exp
+                                        (capture-env (if (pair? env)
+                                                         (cdr (last-pair env))
+                                                         env))))
           (eval x env)))
       
-        (('dynwind (in exp . out))
-         (dynamic-wind (eval in env)
-                       (lambda () (eval exp env))
-                       (eval out env)))
-        
-        (('with-fluids (fluids vals . exp))
-         (let* ((fluids (map (lambda (x) (eval x env)) fluids))
-                (vals (map (lambda (x) (eval x env)) vals)))
-           (let lp ((fluids fluids) (vals vals))
-             (if (null? fluids)
-                 (eval exp env)
-                 (with-fluids (((car fluids) (car vals)))
-                   (lp (cdr fluids) (cdr vals)))))))
-        
-        (('prompt (tag exp . handler))
-         (@prompt (eval tag env)
-                  (eval exp env)
-                  (eval handler env)))
+        (('call-with-prompt (tag thunk . handler))
+         (call-with-prompt
+          (eval tag env)
+          (eval thunk env)
+          (eval handler env)))
         
         (('call/cc proc)
          (call/cc (eval proc env)))
     (lambda (exp)
       "Evaluate @var{exp} in the current module."
       (eval 
-       (if (memoized? exp)
-           exp
-           ((module-transformer (current-module)) exp))
+       (memoize-expression 
+        (if (macroexpanded? exp)
+            exp
+            ((module-transformer (current-module)) exp)))
        '()))))