- currently active non-nil restart name, then a control-error is signalled."
- (let ((real-restart (find-restart restart)))
- (unless real-restart
- (error 'simple-control-error
- :format-control "Restart ~S is not active."
- :format-arguments (list restart)))
- (apply (restart-function real-restart)
- (let ((interactive-function
- (restart-interactive-function real-restart)))
- (if interactive-function
- (funcall interactive-function)
- '())))))
-
-(eval-when (:compile-toplevel :load-toplevel :execute)
-;;; 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 data)
- (let ((exp (macroexpand expression)))
- (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
- (list ,@(mapcar (lambda (da)
- `(find-restart ',(nth 0 da)))
- data))
- ,(if (eq name 'cerror)
- `(cerror ,(second expression) ,n-cond)
- `(,name ,n-cond))))
- expression))
- expression)))
-) ; EVAL-WHEN
-
-;;; 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 restart-case (expression &body clauses)
- #!+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 data)))
- ,@(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 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))))
projects / sbcl.git / blobdiff