0.8.3.3:
[sbcl.git] / src / code / defboot.lisp
index 4f5ff75..2379081 100644 (file)
 \f
 ;;;; various sequencing constructs
 
-(defmacro-mundanely prog (varlist &body body-decls)
-  (multiple-value-bind (body decls) (parse-body body-decls nil)
-    `(block nil
-       (let ,varlist
-        ,@decls
-        (tagbody ,@body)))))
-
-(defmacro-mundanely prog* (varlist &body body-decls)
-  (multiple-value-bind (body decls) (parse-body body-decls nil)
-    `(block nil
-       (let* ,varlist
-        ,@decls
-        (tagbody ,@body)))))
+(flet ((prog-expansion-from-let (varlist body-decls let)
+         (multiple-value-bind (body decls)
+            (parse-body body-decls :doc-string-allowed nil)
+          `(block nil
+             (,let ,varlist
+               ,@decls
+               (tagbody ,@body))))))
+  (defmacro-mundanely prog (varlist &body body-decls)
+    (prog-expansion-from-let varlist body-decls 'let))
+  (defmacro-mundanely prog* (varlist &body body-decls)
+    (prog-expansion-from-let varlist body-decls 'let*)))
 
 (defmacro-mundanely prog1 (result &body body)
   (let ((n-result (gensym)))
              (or (sb!c:maybe-inline-syntactic-closure lambda env)
                  (progn
                    (#+sb-xc-host warn
-                    #-sb-xc-host sb!c:maybe-compiler-note
+                    #-sb-xc-host sb!c:maybe-compiler-notify
                     "lexical environment too hairy, can't inline DEFUN ~S"
                     name)
                    nil)))))
 #-sb-xc-host
 (defun %defun (name def doc)
   (declare (type function def))
-  (declare (type (or null simple-string doc)))
+  (declare (type (or null simple-string) doc))
   (aver (legal-fun-name-p name)) ; should've been checked by DEFMACRO DEFUN
   (when (fboundp name)
     (/show0 "redefining NAME in %DEFUN")
   ;; environment. We spuriously reference the gratuitous variable,
   ;; since we don't want to use IGNORABLE on what might be a special
   ;; var.
-  (multiple-value-bind (forms decls) (parse-body body nil)
+  (multiple-value-bind (forms decls) (parse-body body :doc-string-allowed nil)
     (let ((n-list (gensym)))
       `(do* ((,n-list ,list (cdr ,n-list)))
        ((endp ,n-list)
          (tagbody
             ,@forms))))))
 \f
+;;;; conditions, handlers, restarts
+
+;;; KLUDGE: we PROCLAIM these special here so that we can use restart
+;;; macros in the compiler before the DEFVARs are compiled.
+(sb!xc:proclaim
+ '(special *handler-clusters* *restart-clusters* *condition-restarts*))
+
+(defmacro-mundanely with-condition-restarts
+    (condition-form restarts-form &body body)
+  #!+sb-doc
+  "WITH-CONDITION-RESTARTS Condition-Form Restarts-Form Form*
+   Evaluates the Forms in a dynamic environment where the restarts in the list
+   Restarts-Form are associated with the condition returned by Condition-Form.
+   This allows FIND-RESTART, etc., to recognize restarts that are not related
+   to the error currently being debugged. See also RESTART-CASE."
+  (let ((n-cond (gensym)))
+    `(let ((*condition-restarts*
+           (cons (let ((,n-cond ,condition-form))
+                   (cons ,n-cond
+                         (append ,restarts-form
+                                 (cdr (assoc ,n-cond *condition-restarts*)))))
+                 *condition-restarts*)))
+       ,@body)))
+
+(defmacro-mundanely restart-bind (bindings &body forms)
+  #!+sb-doc
+  "Executes forms in a dynamic context where the given restart bindings are
+   in effect. Users probably want to use RESTART-CASE. When clauses contain
+   the same restart name, FIND-RESTART will find the first such clause."
+  `(let ((*restart-clusters*
+         (cons (list
+                ,@(mapcar (lambda (binding)
+                            (unless (or (car binding)
+                                        (member :report-function
+                                                binding
+                                                :test #'eq))
+                              (warn "Unnamed restart does not have a ~
+                                       report function: ~S"
+                                    binding))
+                            `(make-restart :name ',(car binding)
+                                           :function ,(cadr binding)
+                                           ,@(cddr binding)))
+                          bindings))
+               *restart-clusters*)))
+     ,@forms))
+
+;;; Wrap the RESTART-CASE expression in a WITH-CONDITION-RESTARTS if
+;;; appropriate. Gross, but it's what the book seems to say...
+(defun munge-restart-case-expression (expression env)
+  (let ((exp (sb!xc:macroexpand expression env)))
+    (if (consp exp)
+       (let* ((name (car exp))
+              (args (if (eq name 'cerror) (cddr exp) (cdr exp))))
+         (if (member name '(signal error cerror warn))
+             (once-only ((n-cond `(coerce-to-condition
+                                   ,(first args)
+                                   (list ,@(rest args))
+                                   ',(case name
+                                       (warn 'simple-warning)
+                                       (signal 'simple-condition)
+                                       (t 'simple-error))
+                                   ',name)))
+               `(with-condition-restarts
+                    ,n-cond
+                    (car *restart-clusters*)
+                  ,(if (eq name 'cerror)
+                       `(cerror ,(second expression) ,n-cond)
+                       `(,name ,n-cond))))
+             expression))
+       expression)))
+
+;;; FIXME: I did a fair amount of rearrangement of this code in order to
+;;; get WITH-KEYWORD-PAIRS to work cleanly. This code should be tested..
+(defmacro-mundanely restart-case (expression &body clauses &environment env)
+  #!+sb-doc
+  "(RESTART-CASE form
+   {(case-name arg-list {keyword value}* body)}*)
+   The form is evaluated in a dynamic context where the clauses have special
+   meanings as points to which control may be transferred (see INVOKE-RESTART).
+   When clauses contain the same case-name, FIND-RESTART will find the first
+   such clause. If Expression is a call to SIGNAL, ERROR, CERROR or WARN (or
+   macroexpands into such) then the signalled condition will be associated with
+   the new restarts."
+  (flet ((transform-keywords (&key report interactive test)
+          (let ((result '()))
+            (when report
+              (setq result (list* (if (stringp report)
+                                      `#'(lambda (stream)
+                                           (write-string ,report stream))
+                                      `#',report)
+                                  :report-function
+                                  result)))
+            (when interactive
+              (setq result (list* `#',interactive
+                                  :interactive-function
+                                  result)))
+            (when test
+              (setq result (list* `#',test :test-function result)))
+            (nreverse result)))
+        (parse-keyword-pairs (list keys)
+          (do ((l list (cddr l))
+               (k '() (list* (cadr l) (car l) k)))
+              ((or (null l) (not (member (car l) keys)))
+               (values (nreverse k) l)))))
+    (let ((block-tag (gensym))
+         (temp-var (gensym))
+         (data
+          (macrolet (;; KLUDGE: This started as an old DEFMACRO
+                     ;; WITH-KEYWORD-PAIRS general utility, which was used
+                     ;; only in this one place in the code. It was translated
+                     ;; literally into this MACROLET in order to avoid some
+                     ;; cross-compilation bootstrap problems. It would almost
+                     ;; certainly be clearer, and it would certainly be more
+                     ;; concise, to do a more idiomatic translation, merging
+                     ;; this with the TRANSFORM-KEYWORDS logic above.
+                     ;;   -- WHN 19990925
+                     (with-keyword-pairs ((names expression) &body forms)
+                       (let ((temp (member '&rest names)))
+                         (unless (= (length temp) 2)
+                           (error "&REST keyword is ~:[missing~;misplaced~]."
+                                  temp))
+                         (let* ((key-vars (ldiff names temp))
+                                (keywords (mapcar #'keywordicate key-vars))
+                                (key-var (gensym))
+                                (rest-var (cadr temp)))
+                           `(multiple-value-bind (,key-var ,rest-var)
+                                (parse-keyword-pairs ,expression ',keywords)
+                              (let ,(mapcar (lambda (var keyword)
+                                              `(,var (getf ,key-var
+                                                           ,keyword)))
+                                            key-vars keywords)
+                                ,@forms))))))
+            (mapcar (lambda (clause)
+                      (with-keyword-pairs ((report interactive test
+                                                   &rest forms)
+                                           (cddr clause))
+                        (list (car clause) ;name=0
+                              (gensym) ;tag=1
+                              (transform-keywords :report report ;keywords=2
+                                                  :interactive interactive
+                                                  :test test)
+                              (cadr clause) ;bvl=3
+                              forms))) ;body=4
+                  clauses))))
+      `(block ,block-tag
+        (let ((,temp-var nil))
+          (tagbody
+           (restart-bind
+               ,(mapcar (lambda (datum)
+                          (let ((name (nth 0 datum))
+                                (tag  (nth 1 datum))
+                                (keys (nth 2 datum)))
+                            `(,name #'(lambda (&rest temp)
+                                        (setq ,temp-var temp)
+                                        (go ,tag))
+                                    ,@keys)))
+                        data)
+             (return-from ,block-tag
+                          ,(munge-restart-case-expression expression env)))
+           ,@(mapcan (lambda (datum)
+                       (let ((tag  (nth 1 datum))
+                             (bvl  (nth 3 datum))
+                             (body (nth 4 datum)))
+                         (list tag
+                               `(return-from ,block-tag
+                                  (apply (lambda ,bvl ,@body)
+                                         ,temp-var)))))
+                     data)))))))
+
+(defmacro-mundanely with-simple-restart ((restart-name format-string
+                                                      &rest format-arguments)
+                                        &body forms)
+  #!+sb-doc
+  "(WITH-SIMPLE-RESTART (restart-name format-string format-arguments)
+   body)
+   If restart-name is not invoked, then all values returned by forms are
+   returned. If control is transferred to this restart, it immediately
+   returns the values NIL and T."
+  `(restart-case
+       ;; If there's just one body form, then don't use PROGN. This allows
+       ;; RESTART-CASE to "see" calls to ERROR, etc.
+       ,(if (= (length forms) 1) (car forms) `(progn ,@forms))
+     (,restart-name ()
+       :report (lambda (stream)
+                 (format stream ,format-string ,@format-arguments))
+      (values nil t))))
+
+(defmacro-mundanely handler-bind (bindings &body forms)
+  #!+sb-doc
+  "(HANDLER-BIND ( {(type handler)}* )  body)
+   Executes body in a dynamic context where the given handler bindings are
+   in effect. Each handler must take the condition being signalled as an
+   argument. The bindings are searched first to last in the event of a
+   signalled condition."
+  (let ((member-if (member-if (lambda (x)
+                               (not (proper-list-of-length-p x 2)))
+                             bindings)))
+    (when member-if
+      (error "ill-formed handler binding: ~S" (first member-if))))
+  `(let ((*handler-clusters*
+         (cons (list ,@(mapcar (lambda (x) `(cons ',(car x) ,(cadr x)))
+                               bindings))
+               *handler-clusters*)))
+     (multiple-value-prog1
+        (progn
+          ,@forms)
+       ;; Wait for any float exceptions.
+       #!+x86 (float-wait))))
+
+(defmacro-mundanely handler-case (form &rest cases)
+  "(HANDLER-CASE form
+   { (type ([var]) body) }* )
+   Execute FORM in a context with handlers established for the condition
+   types. A peculiar property allows type to be :NO-ERROR. If such a clause
+   occurs, and form returns normally, all its values are passed to this clause
+   as if by MULTIPLE-VALUE-CALL.  The :NO-ERROR clause accepts more than one
+   var specification."
+  ;; FIXME: Replacing CADR, CDDDR and friends with DESTRUCTURING-BIND
+  ;; and names for the subexpressions would make it easier to
+  ;; understand the code below.
+  (let ((no-error-clause (assoc ':no-error cases)))
+    (if no-error-clause
+       (let ((normal-return (make-symbol "normal-return"))
+             (error-return  (make-symbol "error-return")))
+         `(block ,error-return
+            (multiple-value-call (lambda ,@(cdr no-error-clause))
+              (block ,normal-return
+                (return-from ,error-return
+                  (handler-case (return-from ,normal-return ,form)
+                    ,@(remove no-error-clause cases)))))))
+       (let ((tag (gensym))
+             (var (gensym))
+             (annotated-cases (mapcar (lambda (case) (cons (gensym) case))
+                                      cases)))
+         `(block ,tag
+            (let ((,var nil))
+              (declare (ignorable ,var))
+              (tagbody
+               (handler-bind
+                   ,(mapcar (lambda (annotated-case)
+                              (list (cadr annotated-case)
+                                    `(lambda (temp)
+                                       ,(if (caddr annotated-case)
+                                            `(setq ,var temp)
+                                            '(declare (ignore temp)))
+                                       (go ,(car annotated-case)))))
+                            annotated-cases)
+                 (return-from ,tag
+                   #!-x86 ,form
+                   #!+x86 (multiple-value-prog1 ,form
+                            ;; Need to catch FP errors here!
+                            (float-wait))))
+               ,@(mapcan
+                  (lambda (annotated-case)
+                    (list (car annotated-case)
+                          (let ((body (cdddr annotated-case)))
+                            `(return-from
+                                 ,tag
+                               ,(cond ((caddr annotated-case)
+                                       `(let ((,(caaddr annotated-case)
+                                               ,var))
+                                          ,@body))
+                                      ((not (cdr body))
+                                       (car body))
+                                      (t
+                                       `(progn ,@body)))))))
+                  annotated-cases))))))))
+\f
 ;;;; miscellaneous
 
 (defmacro-mundanely return (&optional (value nil))