0.pre7.101:

[sbcl.git] / src / code / loop.lisp

diff --git a/src/code/loop.lisp b/src/code/loop.lisp
index 9f8ca8a..b3a79ae 100644 (file)
--- a/src/code/loop.lisp
+++ b/src/code/loop.lisp
@@ -328,12 +328,6 @@ code to be loaded.
 \f
 ;;;; SETQ hackery
 
 \f
 ;;;; SETQ hackery
 

-(defvar *loop-destructuring-hooks*
-       nil
-  #!+sb-doc
-  "If not NIL, this must be a list of two things:
-a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.")
-

 (defun loop-make-psetq (frobs)
   (and frobs
        (loop-make-desetq
 (defun loop-make-psetq (frobs)
   (and frobs
        (loop-make-desetq

@@ -345,10 +339,7 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
 (defun loop-make-desetq (var-val-pairs)
   (if (null var-val-pairs)
       nil
 (defun loop-make-desetq (var-val-pairs)
   (if (null var-val-pairs)
       nil

-      (cons (if *loop-destructuring-hooks*
-               (cadr *loop-destructuring-hooks*)
-               'loop-really-desetq)
-           var-val-pairs)))
+      (cons 'loop-really-desetq var-val-pairs)))

 
 (defvar *loop-desetq-temporary*
        (make-symbol "LOOP-DESETQ-TEMP"))
 
 (defvar *loop-desetq-temporary*
        (make-symbol "LOOP-DESETQ-TEMP"))

@@ -581,26 +572,27 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
     (when (or *loop-duplicate-code* (not rbefore))
       (return-from loop-body (makebody)))
     ;; This outer loop iterates once for each not-first-time flag test
     (when (or *loop-duplicate-code* (not rbefore))
       (return-from loop-body (makebody)))
     ;; This outer loop iterates once for each not-first-time flag test

-    ;; generated plus once more for the forms that don't need a flag test
+    ;; generated plus once more for the forms that don't need a flag test.

     (do ((threshold (loop-code-duplication-threshold env))) (nil)
       (declare (fixnum threshold))
     (do ((threshold (loop-code-duplication-threshold env))) (nil)
       (declare (fixnum threshold))

-      ;; Go backwards from the ends of before-loop and after-loop merging all
-      ;; the equivalent forms into the body.
+      ;; Go backwards from the ends of before-loop and after-loop
+      ;; merging all the equivalent forms into the body.

       (do () ((or (null rbefore) (not (equal (car rbefore) (car rafter)))))
        (push (pop rbefore) main-body)
        (pop rafter))
       (unless rbefore (return (makebody)))
       (do () ((or (null rbefore) (not (equal (car rbefore) (car rafter)))))
        (push (pop rbefore) main-body)
        (pop rafter))
       (unless rbefore (return (makebody)))

-      ;; The first forms in RBEFORE & RAFTER (which are the chronologically
-      ;; last forms in the list) differ, therefore they cannot be moved
-      ;; into the main body. If everything that chronologically precedes
-      ;; them either differs or is equal but is okay to duplicate, we can
-      ;; just put all of rbefore in the prologue and all of rafter after
-      ;; the body. Otherwise, there is something that is not okay to
-      ;; duplicate, so it and everything chronologically after it in
-      ;; rbefore and rafter must go into the body, with a flag test to
-      ;; distinguish the first time around the loop from later times.
-      ;; What chronologically precedes the non-duplicatable form will
-      ;; be handled the next time around the outer loop.
+      ;; The first forms in RBEFORE & RAFTER (which are the
+      ;; chronologically last forms in the list) differ, therefore
+      ;; they cannot be moved into the main body. If everything that
+      ;; chronologically precedes them either differs or is equal but
+      ;; is okay to duplicate, we can just put all of rbefore in the
+      ;; prologue and all of rafter after the body. Otherwise, there
+      ;; is something that is not okay to duplicate, so it and
+      ;; everything chronologically after it in rbefore and rafter
+      ;; must go into the body, with a flag test to distinguish the
+      ;; first time around the loop from later times. What
+      ;; chronologically precedes the non-duplicatable form will be
+      ;; handled the next time around the outer loop.

       (do ((bb rbefore (cdr bb))
           (aa rafter (cdr aa))
           (lastdiff nil)
       (do ((bb rbefore (cdr bb))
           (aa rafter (cdr aa))
           (lastdiff nil)

@@ -639,9 +631,9 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
   (if (null expr) 0
       (let ((ans (estimate-code-size expr env)))
        (declare (fixnum ans))
   (if (null expr) 0
       (let ((ans (estimate-code-size expr env)))
        (declare (fixnum ans))

-       ;; @@@@ Use (DECLARATION-INFORMATION 'OPTIMIZE ENV) here to get an
-       ;; alist of optimize quantities back to help quantify how much code we
-       ;; are willing to duplicate.
+       ;; @@@@ Use (DECLARATION-INFORMATION 'OPTIMIZE ENV) here to
+       ;; get an alist of optimize quantities back to help quantify
+       ;; how much code we are willing to duplicate.

        ans)))
 
 (defvar *special-code-sizes*
        ans)))
 
 (defvar *special-code-sizes*

@@ -769,6 +761,12 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
                           specified-type required-type)))
        specified-type)))
 \f
                           specified-type required-type)))
        specified-type)))
 \f

+(defun loop-build-destructuring-bindings (crocks forms)
+  (if crocks
+      `((destructuring-bind ,(car crocks) ,(cadr crocks)
+        ,@(loop-build-destructuring-bindings (cddr crocks) forms)))
+      forms))
+

 (defun loop-translate (*loop-source-code*
                       *loop-macro-environment*
                       *loop-universe*)
 (defun loop-translate (*loop-source-code*
                       *loop-macro-environment*
                       *loop-universe*)

@@ -817,16 +815,10 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
            (let ((forms (list answer)))
              ;;(when crocks (push crocks forms))
              (when dcls (push `(declare ,@dcls) forms))
            (let ((forms (list answer)))
              ;;(when crocks (push crocks forms))
              (when dcls (push `(declare ,@dcls) forms))

-             (setq answer `(,(cond ((not vars) 'locally)
-                                   (*loop-destructuring-hooks*
-                                    (first *loop-destructuring-hooks*))
-                                   (t
-                                    'let))
+             (setq answer `(,(if vars 'let 'locally)

                             ,vars
                             ,vars

-                            ,@(if crocks
-                                  `((destructuring-bind ,@crocks
-                                        ,@forms))
-                                forms)))))))
+                            ,@(loop-build-destructuring-bindings crocks
+                                                                 forms)))))))

       answer)))
 
 (defun loop-iteration-driver ()
       answer)))
 
 (defun loop-iteration-driver ()

@@ -861,17 +853,25 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
       (pop *loop-source-code*)
       (loop-error "LOOP source code ran out when another token was expected.")))
 
       (pop *loop-source-code*)
       (loop-error "LOOP source code ran out when another token was expected.")))
 

-(defun loop-get-progn ()
-  (do ((forms (list (loop-pop-source)) (cons (loop-pop-source) forms))
-       (nextform (car *loop-source-code*) (car *loop-source-code*)))
-      ((atom nextform)
-       (if (null (cdr forms)) (car forms) (cons 'progn (nreverse forms))))))
-

 (defun loop-get-form ()
   (if *loop-source-code*
       (loop-pop-source)
       (loop-error "LOOP code ran out where a form was expected.")))
 
 (defun loop-get-form ()
   (if *loop-source-code*
       (loop-pop-source)
       (loop-error "LOOP code ran out where a form was expected.")))
 

+(defun loop-get-compound-form ()
+  (let ((form (loop-get-form)))
+    (unless (consp form)
+      (loop-error "A compound form was expected, but ~S found." form))
+    form))
+
+(defun loop-get-progn ()
+  (do ((forms (list (loop-get-compound-form))
+              (cons (loop-get-compound-form) forms))
+       (nextform (car *loop-source-code*)
+                 (car *loop-source-code*)))
+      ((atom nextform)
+       (if (null (cdr forms)) (car forms) (cons 'progn (nreverse forms))))))
+

 (defun loop-construct-return (form)
   `(return-from ,(car *loop-names*) ,form))
 
 (defun loop-construct-return (form)
   `(return-from ,(car *loop-names*) ,form))
 

@@ -910,17 +910,18 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
   (and *loop-source-code* ; Don't get confused by NILs..
        (let ((z (car *loop-source-code*)))
         (cond ((loop-tequal z 'of-type)
   (and *loop-source-code* ; Don't get confused by NILs..
        (let ((z (car *loop-source-code*)))
         (cond ((loop-tequal z 'of-type)

-               ;; This is the syntactically unambigous form in that the form
-               ;; of the type specifier does not matter. Also, it is assumed
-               ;; that the type specifier is unambiguously, and without need
-               ;; of translation, a common lisp type specifier or pattern
-               ;; (matching the variable) thereof.
+               ;; This is the syntactically unambigous form in that
+               ;; the form of the type specifier does not matter.
+               ;; Also, it is assumed that the type specifier is
+               ;; unambiguously, and without need of translation, a
+               ;; common lisp type specifier or pattern (matching the
+               ;; variable) thereof.

                (loop-pop-source)
                (loop-pop-source))
 
               ((symbolp z)
                (loop-pop-source)
                (loop-pop-source))
 
               ((symbolp z)

-               ;; This is the (sort of) "old" syntax, even though we didn't
-               ;; used to support all of these type symbols.
+               ;; This is the (sort of) "old" syntax, even though we
+               ;; didn't used to support all of these type symbols.

                (let ((type-spec (or (gethash z
                                              (loop-universe-type-symbols
                                               *loop-universe*))
                (let ((type-spec (or (gethash z
                                              (loop-universe-type-symbols
                                               *loop-universe*))

@@ -931,11 +932,12 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
                    (loop-pop-source)
                    type-spec)))
               (t
                    (loop-pop-source)
                    type-spec)))
               (t

-               ;; This is our sort-of old syntax. But this is only valid for
-               ;; when we are destructuring, so we will be compulsive (should
-               ;; we really be?) and require that we in fact be doing variable
-               ;; destructuring here. We must translate the old keyword
-               ;; pattern typespec into a fully-specified pattern of real type
+               ;; This is our sort-of old syntax. But this is only
+               ;; valid for when we are destructuring, so we will be
+               ;; compulsive (should we really be?) and require that
+               ;; we in fact be doing variable destructuring here. We
+               ;; must translate the old keyword pattern typespec
+               ;; into a fully-specified pattern of real type

                ;; specifiers here.
                (if (consp variable)
                    (unless (consp z)
                ;; specifiers here.
                (if (consp variable)
                    (unless (consp z)

@@ -1009,14 +1011,12 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
         (push (list name (or initialization (loop-typed-init dtype)))
               *loop-variables*))
        (initialization
         (push (list name (or initialization (loop-typed-init dtype)))
               *loop-variables*))
        (initialization

-        (cond (*loop-destructuring-hooks*
-               (loop-declare-variable name dtype)
-               (push (list name initialization) *loop-variables*))
-              (t (let ((newvar (gensym "LOOP-DESTRUCTURE-")))
-                   (push (list newvar initialization) *loop-variables*)
-                   ;; *LOOP-DESETQ-CROCKS* gathered in reverse order.
-                   (setq *loop-desetq-crocks*
-                     (list* name newvar *loop-desetq-crocks*))))))
+        (let ((newvar (gensym "LOOP-DESTRUCTURE-")))
+           (loop-declare-variable name dtype)
+           (push (list newvar initialization) *loop-variables*)
+           ;; *LOOP-DESETQ-CROCKS* gathered in reverse order.
+           (setq *loop-desetq-crocks*
+                 (list* name newvar *loop-desetq-crocks*))))

        (t (let ((tcar nil) (tcdr nil))
             (if (atom dtype) (setq tcar (setq tcdr dtype))
                 (setq tcar (car dtype) tcdr (cdr dtype)))
        (t (let ((tcar nil) (tcdr nil))
             (if (atom dtype) (setq tcar (setq tcdr dtype))
                 (setq tcar (car dtype) tcdr (cdr dtype)))

@@ -1377,11 +1377,11 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
 \f
 ;;;; various FOR/AS subdispatches
 
 \f
 ;;;; various FOR/AS subdispatches
 

-;;; ANSI "FOR x = y [THEN z]" is sort of like the old Genera one when the THEN
-;;; is omitted (other than being more stringent in its placement), and like the
-;;; old "FOR x FIRST y THEN z" when the THEN is present. I.e., the first
-;;; initialization occurs in the loop body (first-step), not in the variable
-;;; binding phase.
+;;; ANSI "FOR x = y [THEN z]" is sort of like the old Genera one when
+;;; the THEN is omitted (other than being more stringent in its
+;;; placement), and like the old "FOR x FIRST y THEN z" when the THEN
+;;; is present. I.e., the first initialization occurs in the loop body
+;;; (first-step), not in the variable binding phase.

 (defun loop-ansi-for-equals (var val data-type)
   (loop-make-iteration-variable var nil data-type)
   (cond ((loop-tequal (car *loop-source-code*) :then)
 (defun loop-ansi-for-equals (var val data-type)
   (loop-make-iteration-variable var nil data-type)
   (cond ((loop-tequal (car *loop-source-code*) :then)

@@ -1427,9 +1427,9 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
 ;;;; list iteration
 
 (defun loop-list-step (listvar)
 ;;;; list iteration
 
 (defun loop-list-step (listvar)

-  ;; We are not equipped to analyze whether 'FOO is the same as #'FOO here in
-  ;; any sensible fashion, so let's give an obnoxious warning whenever 'FOO is
-  ;; used as the stepping function.
+  ;; We are not equipped to analyze whether 'FOO is the same as #'FOO
+  ;; here in any sensible fashion, so let's give an obnoxious warning
+  ;; whenever 'FOO is used as the stepping function.

   ;;
   ;; While a Discerning Compiler may deal intelligently with
   ;; (FUNCALL 'FOO ...), not recognizing FOO may defeat some LOOP
   ;;
   ;; While a Discerning Compiler may deal intelligently with
   ;; (FUNCALL 'FOO ...), not recognizing FOO may defeat some LOOP

@@ -1565,8 +1565,8 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
                      (apply fun var data-type preps user-data))))
     (when *loop-named-variables*
       (loop-error "Unused USING variables: ~S." *loop-named-variables*))
                      (apply fun var data-type preps user-data))))
     (when *loop-named-variables*
       (loop-error "Unused USING variables: ~S." *loop-named-variables*))

-    ;; STUFF is now (bindings prologue-forms . stuff-to-pass-back). Protect the
-    ;; system from the user and the user from himself.
+    ;; STUFF is now (bindings prologue-forms . stuff-to-pass-back).
+    ;; Protect the system from the user and the user from himself.

     (unless (member (length stuff) '(6 10))
       (loop-error "Value passed back by LOOP iteration path function for path ~S has invalid length."
                  path))
     (unless (member (length stuff) '(6 10))
       (loop-error "Value passed back by LOOP iteration path function for path ~S has invalid length."
                  path))

@@ -1640,11 +1640,11 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
 \f
 ;;;; master sequencer function
 
 \f
 ;;;; master sequencer function
 

-(defun loop-sequencer (indexv indexv-type indexv-user-specified-p
-                         variable variable-type
-                         sequence-variable sequence-type
-                         step-hack default-top
-                         prep-phrases)
+(defun loop-sequencer (indexv indexv-type 
+                      variable variable-type
+                      sequence-variable sequence-type
+                      step-hack default-top
+                      prep-phrases)

    (let ((endform nil) ; Form (constant or variable) with limit value
         (sequencep nil) ; T if sequence arg has been provided
         (testfn nil) ; endtest function
    (let ((endform nil) ; Form (constant or variable) with limit value
         (sequencep nil) ; T if sequence arg has been provided
         (testfn nil) ; endtest function

@@ -1752,11 +1752,11 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
 
 (defun loop-for-arithmetic (var val data-type kwd)
   (loop-sequencer
 
 (defun loop-for-arithmetic (var val data-type kwd)
   (loop-sequencer

-    var (loop-check-data-type data-type 'real) t
-    nil nil nil nil nil nil
-    (loop-collect-prepositional-phrases
-      '((:from :upfrom :downfrom) (:to :upto :downto :above :below) (:by))
-      nil (list (list kwd val)))))
+   var (loop-check-data-type data-type 'real)
+   nil nil nil nil nil nil
+   (loop-collect-prepositional-phrases
+    '((:from :upfrom :downfrom) (:to :upto :downto :above :below) (:by))
+    nil (list (list kwd val)))))

 
 (defun loop-sequence-elements-path (variable data-type prep-phrases
                                    &key
 
 (defun loop-sequence-elements-path (variable data-type prep-phrases
                                    &key

@@ -1764,16 +1764,16 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
                                    size-function
                                    sequence-type
                                    element-type)
                                    size-function
                                    sequence-type
                                    element-type)

-  (multiple-value-bind (indexv indexv-user-specified-p) (named-variable 'index)
+  (multiple-value-bind (indexv) (named-variable 'index)

     (let ((sequencev (named-variable 'sequence)))
       (list* nil nil                           ; dummy bindings and prologue
             (loop-sequencer
     (let ((sequencev (named-variable 'sequence)))
       (list* nil nil                           ; dummy bindings and prologue
             (loop-sequencer

-              indexv 'fixnum indexv-user-specified-p
-              variable (or data-type element-type)
-              sequencev sequence-type
-              `(,fetch-function ,sequencev ,indexv)
-              `(,size-function ,sequencev)
-              prep-phrases)))))
+             indexv 'fixnum 
+             variable (or data-type element-type)
+             sequencev sequence-type
+             `(,fetch-function ,sequencev ,indexv)
+             `(,size-function ,sequencev)
+             prep-phrases)))))

 \f
 ;;;; builtin LOOP iteration paths
 
 \f
 ;;;; builtin LOOP iteration paths
 

@@ -1785,7 +1785,7 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
 ||#
 
 (defun loop-hash-table-iteration-path (variable data-type prep-phrases
 ||#
 
 (defun loop-hash-table-iteration-path (variable data-type prep-phrases

-                                      &key (which (required-argument)))
+                                      &key (which (missing-arg)))

   (declare (type (member :hash-key :hash-value) which))
   (cond ((or (cdr prep-phrases) (not (member (caar prep-phrases) '(:in :of))))
         (loop-error "too many prepositions!"))
   (declare (type (member :hash-key :hash-value) which))
   (cond ((or (cdr prep-phrases) (not (member (caar prep-phrases) '(:in :of))))
         (loop-error "too many prepositions!"))

@@ -1796,12 +1796,14 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
        (dummy-predicate-var nil)
        (post-steps nil))
     (multiple-value-bind (other-var other-p)
        (dummy-predicate-var nil)
        (post-steps nil))
     (multiple-value-bind (other-var other-p)

-       (named-variable (if (eq which 'hash-key) 'hash-value 'hash-key))
-      ;; @@@@ named-variable returns a second value of T if the name was
-      ;; actually specified, so clever code can throw away the gensym'ed up
-      ;; variable if it isn't really needed. The following is for those
-      ;; implementations in which we cannot put dummy NILs into
-      ;; multiple-value-setq variable lists.
+       (named-variable (ecase which
+                         (:hash-key 'hash-value)
+                         (:hash-value 'hash-key)))
+      ;; @@@@ NAMED-VARIABLE returns a second value of T if the name
+      ;; was actually specified, so clever code can throw away the
+      ;; GENSYM'ed-up variable if it isn't really needed. The
+      ;; following is for those implementations in which we cannot put
+      ;; dummy NILs into MULTIPLE-VALUE-SETQ variable lists.

       (setq other-p t
            dummy-predicate-var (loop-when-it-variable))
       (let ((key-var nil)
       (setq other-p t
            dummy-predicate-var (loop-when-it-variable))
       (let ((key-var nil)

@@ -1809,9 +1811,11 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
            (bindings `((,variable nil ,data-type)
                        (,ht-var ,(cadar prep-phrases))
                        ,@(and other-p other-var `((,other-var nil))))))
            (bindings `((,variable nil ,data-type)
                        (,ht-var ,(cadar prep-phrases))
                        ,@(and other-p other-var `((,other-var nil))))))

-       (if (eq which 'hash-key)
-           (setq key-var variable val-var (and other-p other-var))
-           (setq key-var (and other-p other-var) val-var variable))
+       (ecase which
+         (:hash-key (setq key-var variable
+                          val-var (and other-p other-var)))
+         (:hash-value (setq key-var (and other-p other-var)
+                            val-var variable)))

        (push `(with-hash-table-iterator (,next-fn ,ht-var)) *loop-wrappers*)
        (when (consp key-var)
          (setq post-steps
        (push `(with-hash-table-iterator (,next-fn ,ht-var)) *loop-wrappers*)
        (when (consp key-var)
          (setq post-steps

@@ -1899,6 +1903,7 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
                             (below (loop-for-arithmetic :below))
                             (to (loop-for-arithmetic :to))
                             (upto (loop-for-arithmetic :upto))
                             (below (loop-for-arithmetic :below))
                             (to (loop-for-arithmetic :to))
                             (upto (loop-for-arithmetic :upto))

+                            (by (loop-for-arithmetic :by))

                             (being (loop-for-being)))
             :iteration-keywords '((for (loop-do-for))
                                   (as (loop-do-for))
                             (being (loop-for-being)))
             :iteration-keywords '((for (loop-do-for))
                                   (as (loop-do-for))

@@ -1937,7 +1942,8 @@ a LET-like macro, and a SETQ-like macro, which perform LOOP-style destructuring.
                   'loop-package-symbols-iteration-path w
                   :preposition-groups '((:of :in))
                   :inclusive-permitted nil
                   'loop-package-symbols-iteration-path w
                   :preposition-groups '((:of :in))
                   :inclusive-permitted nil

-                  :user-data '(:symbol-types (:internal)))
+                  :user-data '(:symbol-types (:internal
+                                              :external)))

     w))
 
 (defparameter *loop-ansi-universe*
     w))
 
 (defparameter *loop-ansi-universe*