[COMMIT] Improve the lexical scoping in #'block, #'return-from.

APPROVE COMMIT NOTE: This patch has been committed. # HG changeset patch # User Aidan Kehoe <kehoea(a)parhasard.net&gt; # Date 1297080084 0 # Node ID 38e24b8be4eaeafc13229ca02d7d8bbd2a6449c7 # Parent cc7d0e19173c5384d783047ef1aeb95f5dc04e90 Improve the lexical scoping in #'block, #'return-from. lisp/ChangeLog addition: 2011-02-07 Aidan Kehoe <kehoea(a)parhasard.net&gt; * bytecomp.el: * bytecomp.el (byte-compile-initial-macro-environment): Shadow `block', `return-from' here, we implement them differently when byte-compiling. * bytecomp.el (byte-compile-active-blocks): New. * bytecomp.el (byte-compile-block-1): New. * bytecomp.el (byte-compile-return-from-1): New. * bytecomp.el (return-from-1): New. * bytecomp.el (block-1): New. These are two aliases that exist to have their own associated byte-compile functions, which functions implement `block' and `return-from'. * cl-extra.el (cl-macroexpand-all): Fix a bug here when macros in the environment have been compiled. * cl-macs.el (block): * cl-macs.el (return): * cl-macs.el (return-from): Be more careful about lexical scope in these macros. * cl.el: * cl.el ('cl-block-wrapper): Removed. * cl.el ('cl-block-throw): Removed. These aren't needed in code generated by this XEmacs. They shouldn't be needed in code generated by XEmacs 21.4, but if it turns out the packages do need them, we can put them back. 2011-01-30 Mike Sperber <mike(a)xemacs.org&gt; * font-lock.el (font-lock-fontify-pending-extents): Don't fail if `font-lock-mode' is unset, which can happen in the middle of `revert-buffer'. 2011-01-23 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-macs.el (delete): * cl-macs.el (delq): * cl-macs.el (remove): * cl-macs.el (remq): Don't use the compiler macro if these functions were given the wrong number of arguments, as happens in lisp-tests.el. * cl-seq.el (remove, remq): Removed. I added these to subr.el, and forgot to remove them from here. 2011-01-22 Aidan Kehoe <kehoea(a)parhasard.net&gt; * bytecomp.el (byte-compile-setq, byte-compile-set): Remove kludge allowing keywords' values to be set, all the code that does that is gone. * cl-compat.el (elt-satisfies-test-p): * faces.el (set-face-parent): * faces.el (face-doc-string): * gtk-font-menu.el: * gtk-font-menu.el (gtk-reset-device-font-menus): * msw-font-menu.el: * msw-font-menu.el (mswindows-reset-device-font-menus): * package-get.el (package-get-installedp): * select.el (select-convert-from-image-data): * sound.el: * sound.el (load-sound-file): * x-font-menu.el (x-reset-device-font-menus-core): Don't quote keywords, they're self-quoting, and the win from backward-compatibility is sufficiently small now that the style problem overrides it. 2011-01-22 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-macs.el (block, return-from): Require that NAME be a symbol in these macros, as always documented in the #'block docstring and as required by Common Lisp. * descr-text.el (unidata-initialize-unihan-database): Correct the use of non-symbols in #'block and #'return-from in this function. 2011-01-15 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-extra.el (concatenate): Accept more complicated TYPEs in this function, handing the sequences over to #'coerce if we don't understand them here. * cl-macs.el (inline): Don't proclaim #'concatenate as inline, its compiler macro is more useful than doing that. 2011-01-11 Aidan Kehoe <kehoea(a)parhasard.net&gt; * subr.el (delete, delq, remove, remq): Move #'remove, #'remq here, they don't belong in cl-seq.el; move #'delete, #'delq here from fns.c, implement them in terms of #'delete*, allowing support for sequences generally. * update-elc.el (do-autoload-commands): Use #'delete*, not #'delq here, now the latter's no longer dumped. * cl-macs.el (delete, delq): Add compiler macros transforming #'delete and #'delq to #'delete* calls. 2011-01-10 Aidan Kehoe <kehoea(a)parhasard.net&gt; * dialog.el (make-dialog-box): Correct a misplaced parenthesis here, thank you Mats Lidell in 87zkr9gqrh.fsf(a)mail.contactor.se ! 2011-01-02 Aidan Kehoe <kehoea(a)parhasard.net&gt; * dialog.el (make-dialog-box): * list-mode.el (display-completion-list): These functions used to use cl-parsing-keywords; change them to use defun* instead, fixing the build. (Not sure what led to me not including this change in d1b17a33450b!) 2011-01-02 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-macs.el (define-star-compiler-macros): Make sure the form has ITEM and LIST specified before attempting to change to calls with explicit tests; necessary for some tests in lisp-tests.el to compile correctly. (stable-union, stable-intersection): Add compiler macros for these functions, in the same way we do for most of the other functions in cl-seq.el. 2011-01-01 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-macs.el (dolist, dotimes, do-symbols, macrolet) (symbol-macrolet): Define these macros with defmacro* instead of parsing the argument list by hand, for the sake of style and readability; use backquote where appropriate, instead of calling #'list and and friends, for the same reason. 2010-12-30 Aidan Kehoe <kehoea(a)parhasard.net&gt; * x-misc.el (device-x-display): Provide this function, documented in the Lispref for years, but not existing previously. Thank you Julian Bradfield, thank you Jeff Mincy. 2010-12-30 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-seq.el: Move the heavy lifting from this file to C. Dump the cl-parsing-keywords macro, but don't use defun* for the functions we define that do take keywords, dynamic scope lossage makes that not practical. * subr.el (sort, fillarray): Move these aliases here. (map-plist): #'nsublis is now built-in, but at this point #'eql isn't necessarily available as a test; use #'eq. * obsolete.el (cl-delete-duplicates): Make this available for old compiler macros and old code. (memql): Document that this is equivalent to #'member*, and worse. * cl.el (adjoin, subst): Removed. These are in C. 2010-12-30 Aidan Kehoe <kehoea(a)parhasard.net&gt; * simple.el (assoc-ignore-case): Remove a duplicate definition of this function (it's already in subr.el). * iso8859-1.el (char-width): On non-Mule, make this function equivalent to that produced by (constantly 1), but preserve its docstring. * subr.el (subst-char-in-string): Define this in terms of #'substitute, #'nsubstitute. (string-width): Define this using #'reduce and #'char-width. (char-width): Give this a simpler definition, it makes far more sense to check for mule at load time and redefine, as we do in iso8859-1.el. (store-substring): Implement this in terms of #'replace, now #'replace is cheap. 2010-12-30 Aidan Kehoe <kehoea(a)parhasard.net&gt; * update-elc.el (lisp-files-needed-for-byte-compilation) (lisp-files-needing-early-byte-compilation): cl-macs belongs in the former, not the latter, it is as fundamental as bytecomp.el. 2010-12-30 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl.el: Provde the Common Lisp program-error, type-error as error symbols. This doesn't nearly go far enough for anyone using the Common Lisp errors. 2010-12-29 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-macs.el (delete-duplicates): If the form has an incorrect number of arguments, don't attempt a compiler macroexpansion. 2010-12-29 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-macs.el (cl-safe-expr-p): Forms that start with the symbol lambda are also safe. 2010-12-29 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-macs.el (= < > <= >=): For these functions' compiler macros, the optimisation is safe even if the first and the last arguments have side effects, since they're only used the once. 2010-12-29 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-macs.el (inline-side-effect-free-compiler-macros): Unroll a loop here at macro-expansion time, so these compiler macros are compiled. Use #'eql instead of #'eq in a couple of places for better style. 2010-12-29 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-extra.el (notany, notevery): Avoid some dynamic scope stupidity with local variable names in these functions, when they weren't prefixed with cl-; go into some more detail in the doc strings. 2010-12-29 Aidan Kehoe <kehoea(a)parhasard.net&gt; * byte-optimize.el (side-effect-free-fns): #'remove, #'remq are free of side-effects. (side-effect-and-error-free-fns): Drop dot, dot-marker from the list. 2010-11-17 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-extra.el (coerce): In the argument list, name the first argument OBJECT, not X; the former name was always used in the doc string and is clearer. Handle vector type specifications which include the length of the target sequence, error if there's a mismatch. * cl-macs.el (cl-make-type-test): Handle type specifications starting with the symbol 'eql. 2010-11-14 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-macs.el (eql): Don't remove the byte-compile property of this symbol. That was necessary to override a bug in bytecomp.el where #'eql was confused with #'eq, which bug we no longer have. If neither expression is constant, don't attempt to handle the expression in this compiler macro, leave it to byte-compile-eql, which produces better code anyway. * bytecomp.el (eq): #'eql is not the function associated with the byte-eq byte code. (byte-compile-eql): Add an explicit compile method for this function, for cases where the cl-macs compiler macro hasn't reduced it to #'eq or #'equal. 2010-10-25 Aidan Kehoe <kehoea(a)parhasard.net&gt; Add compiler macros and compilation sanity-checking for various functions that take keywords. * byte-optimize.el (side-effect-free-fns): #'symbol-value is side-effect free and not error free. * bytecomp.el (byte-compile-normal-call): Check keyword argument lists for sanity; store information about the positions where keyword arguments start using the new byte-compile-keyword-start property. * cl-macs.el (cl-const-expr-val): Take a new optional argument, cl-not-constant, defaulting to nil, in this function; return it if the expression is not constant. (cl-non-fixnum-number-p): Make this into a separate function, we want to pass it to #'every. (eql): Use it. (define-star-compiler-macros): Use the same code to generate the member*, assoc* and rassoc* compiler macros; special-case some code in #'add-to-list in subr.el. (remove, remq): Add compiler macros for these two functions, in preparation for #'remove being in C. (define-foo-if-compiler-macros): Transform (remove-if-not ...) calls to (remove ... :if-not) at compile time, which will be a real win once the latter is in C. (define-substitute-if-compiler-macros) (define-subst-if-compiler-macros): Similarly for these functions. (delete-duplicates): Change this compiler macro to use #'plists-equal; if we don't have information about the type of SEQUENCE at compile time, don't bother attempting to inline the call, the function will be in C soon enough. (equalp): Remove an old commented-out compiler macro for this, if we want to see it it's in version control. (subst-char-in-string): Transform this to a call to nsubstitute or nsubstitute, if that is appropriate. * cl.el (ldiff): Don't call setf here, this makes for a load-time dependency problem in cl-macs.el 2010-06-14 Stephen J. Turnbull <stephen(a)xemacs.org&gt; * term/vt100.el: Refer to XEmacs, not GNU Emacs, in permissions. * term/bg-mouse.el: * term/sup-mouse.el: Put copyright notice in canonical "Copyright DATE AUTHOR" form. Refer to XEmacs, not GNU Emacs, in permissions. * site-load.el: Add permission boilerplate. * mule/canna-leim.el: * alist.el: Refer to XEmacs, not APEL/this program, in permissions. * mule/canna-leim.el: Remove my copyright, I've assigned it to the FSF. 2010-06-14 Stephen J. Turnbull <stephen(a)xemacs.org&gt; * gtk.el: * gtk-widget-accessors.el: * gtk-package.el: * gtk-marshal.el: * gtk-compose.el: * gnome.el: Add copyright notice based on internal evidence. 2010-06-14 Stephen J. Turnbull <stephen(a)xemacs.org&gt; * easymenu.el: Add reference to COPYING to permission notice. * gutter.el: * gutter-items.el: * menubar-items.el: Fix typo "Xmacs" in permissions notice. 2010-06-14 Stephen J. Turnbull <stephen(a)xemacs.org&gt; * auto-save.el: * font.el: * fontconfig.el: * mule/kinsoku.el: Add "part of XEmacs" text to permission notice. 2010-10-14 Aidan Kehoe <kehoea(a)parhasard.net&gt; * byte-optimize.el (side-effect-free-fns): * cl-macs.el (remf, getf): * cl-extra.el (tailp, cl-set-getf, cl-do-remf): * cl.el (ldiff, endp): Tighten up Common Lisp compatibility for #'ldiff, #'endp, #'tailp; add circularity checking for the first two. #'cl-set-getf and #'cl-do-remf were Lisp implementations of #'plist-put and #'plist-remprop; change the names to aliases, changes the macros that use them to using #'plist-put and #'plist-remprop directly. 2010-10-12 Aidan Kehoe <kehoea(a)parhasard.net&gt; * abbrev.el (fundamental-mode-abbrev-table, global-abbrev-table): Create both these abbrev tables using the usual #'define-abbrev-table calls, rather than attempting to special-case them. * cl-extra.el: Force cl-macs to be loaded here, if cl-extra.el is being loaded interpreted. Previously other, later files would redundantly call (load "cl-macs") when interpreted, it's more reasonable to do it here, once. * cmdloop.el (read-quoted-char-radix): Use defcustom here, we don't have any dump-order dependencies that would prevent that. * custom.el (eval-when-compile): Don't load cl-macs when interpreted or when byte-compiling, rely on cl-extra.el in the former case and the appropriate entry in bytecomp-load-hook in the latter. Get rid of custom-declare-variable-list, we have no dump-time dependencies that would require it. * faces.el (eval-when-compile): Don't load cl-macs when interpreted or when byte-compiling. * packages.el: Remove some inaccurate comments. * post-gc.el (cleanup-simple-finalizers): Use #'delete-if-not here, now the order of preloaded-file-list has been changed to make it available. * subr.el (custom-declare-variable-list): Remove. No need for it. Also remove a stub define-abbrev-table from this file, given the current order of preloaded-file-list there's no need for it. 2010-10-10 Aidan Kehoe <kehoea(a)parhasard.net&gt; * bytecomp.el (byte-compile-constp) Forms quoted with FUNCTION are also constant. (byte-compile-initial-macro-environment): In #'the, if FORM is constant and does not match TYPE, warn at byte-compile time. 2010-10-10 Aidan Kehoe <kehoea(a)parhasard.net&gt; * backquote.el (bq-vector-contents, bq-list*): Remove; the former is equivalent to (append VECTOR nil), the latter to (list* ...). (bq-process-2): Use (append VECTOR nil) instead of using #'bq-vector-contents to convert to a list. (bq-process-1): Now we use list* instead of bq-list * subr.el (list*): Moved from cl.el, since it is now required to be available the first time a backquoted form is encountered. * cl.el (list*): Move to subr.el. 2010-09-16 Aidan Kehoe <kehoea(a)parhasard.net&gt; * test-harness.el (Check-Message): Add an omitted comma here, thank you the buildbot. 2010-09-16 Aidan Kehoe <kehoea(a)parhasard.net&gt; * hash-table.el (hash-table-key-list, hash-table-value-list) (hash-table-key-value-alist, hash-table-key-value-plist): Remove some useless #'nreverse calls in these files; our hash tables have no order, it's not helpful to pretend they do. * behavior.el (read-behavior): Do the same in this file, in some code evidently copied from hash-table.el. 2010-09-16 Aidan Kehoe <kehoea(a)parhasard.net&gt; * info.el (Info-insert-dir): * format.el (format-deannotate-region): * files.el (cd, save-buffers-kill-emacs): Use #'some, #'every and related functions for applying boolean operations to lists, instead of rolling our own ones that cons and don't short-circuit. 2010-09-16 Aidan Kehoe <kehoea(a)parhasard.net&gt; * bytecomp.el (byte-compile-initial-macro-environment): * cl-macs.el (the): Rephrase the docstring, make its implementation when compiling files a little nicer. 2010-09-16 Aidan Kehoe <kehoea(a)parhasard.net&gt; * descr-text.el (unidata-initialize-unicodedata-database) (unidata-initialize-unihan-database, describe-char-unicode-data) (describe-char-unicode-data): Wrap calls to the database functions with (with-fboundp ...), avoiding byte compile warnings on builds without support for the database functions. (describe-char): (reduce #'max ...), not (apply #'max ...), no need to cons needlessly. (describe-char): Remove a redundant lambda wrapping #'extent-properties. (describe-char-unicode-data): Call #'nsubst when replacing "" with nil in the result of #'split-string, instead of consing inside mapcar. 2010-09-16 Aidan Kehoe <kehoea(a)parhasard.net&gt; * x-faces.el (x-available-font-sizes): * specifier.el (let-specifier): * package-ui.el (pui-add-required-packages): * msw-faces.el (mswindows-available-font-sizes): * modeline.el (modeline-minor-mode-menu): * minibuf.el (minibuf-directory-files): Replace the O2N (delq nil (mapcar (lambda (W) (and X Y)) Z)) with the ON (mapcan (lambda (W) (and X (list Y))) Z) in these files. 2010-09-16 Aidan Kehoe <kehoea(a)parhasard.net&gt; * cl-macs.el (= < > <= >=): When these functions are handed more than two arguments, and those arguments have no side effects, transform to a series of two argument calls, avoiding funcall in the byte-compiled code. * mule/mule-cmds.el (finish-set-language-environment): Take advantage of this change in a function called 256 times at startup. 2010-09-16 Aidan Kehoe <kehoea(a)parhasard.net&gt; * bytecomp.el (byte-compile-function-form, byte-compile-quote) (byte-compile-quote-form): Warn at compile time, and error at runtime, if a (quote ...) or a (function ...) form attempts to quote more than one object. 2010-09-16 Aidan Kehoe <kehoea(a)parhasard.net&gt; * byte-optimize.el (byte-optimize-apply): Transform (apply 'nconc (mapcar ...)) to (mapcan ...); warn about use of the first idiom. * update-elc.el (do-autoload-commands): * packages.el (packages-find-package-library-path): * frame.el (frame-list): * extents.el (extent-descendants): * etags.el (buffer-tag-table-files): * dumped-lisp.el (preloaded-file-list): * device.el (device-list): * bytecomp-runtime.el (proclaim-inline, proclaim-notinline) Use #'mapcan, not (apply #'nconc (mapcar ...) in all these files. * bytecomp-runtime.el (eval-when-compile, eval-and-compile): In passing, mention that these macros also evaluate the body when interpreted. tests/ChangeLog addition: 2011-02-07 Aidan Kehoe <kehoea(a)parhasard.net&gt; * automated/lisp-tests.el: Test lexical scope for `block', `return-from'; add a Known-Bug-Expect-Failure for a contorted example that fails when byte-compiled. diff -r cc7d0e19173c -r 38e24b8be4ea lisp/ChangeLog --- a/lisp/ChangeLog Mon Feb 07 00:03:41 2011 +0000 +++ b/lisp/ChangeLog Mon Feb 07 12:01:24 2011 +0000 ＠＠ -1,3 +1,34 ＠＠ +2011-02-07 Aidan Kehoe <kehoea(a)parhasard.net&gt; + + * bytecomp.el: + * bytecomp.el (byte-compile-initial-macro-environment): + Shadow `block', `return-from' here, we implement them differently + when byte-compiling. + + * bytecomp.el (byte-compile-active-blocks): New. + * bytecomp.el (byte-compile-block-1): New. + * bytecomp.el (byte-compile-return-from-1): New. + * bytecomp.el (return-from-1): New. + * bytecomp.el (block-1): New. + These are two aliases that exist to have their own associated + byte-compile functions, which functions implement `block' and + `return-from'. + + * cl-extra.el (cl-macroexpand-all): + Fix a bug here when macros in the environment have been compiled. + + * cl-macs.el (block): + * cl-macs.el (return): + * cl-macs.el (return-from): + Be more careful about lexical scope in these macros. + + * cl.el: + * cl.el ('cl-block-wrapper): Removed. + * cl.el ('cl-block-throw): Removed. + These aren't needed in code generated by this XEmacs. They + shouldn't be needed in code generated by XEmacs 21.4, but if it + turns out the packages do need them, we can put them back. + 2011-01-30 Mike Sperber <mike(a)xemacs.org&gt; * font-lock.el (font-lock-fontify-pending-extents): Don't fail if diff -r cc7d0e19173c -r 38e24b8be4ea lisp/bytecomp.el --- a/lisp/bytecomp.el Mon Feb 07 00:03:41 2011 +0000 +++ b/lisp/bytecomp.el Mon Feb 07 12:01:24 2011 +0000 ＠＠ -511,7 +511,11 ＠＠ "%s is not of type %s" form type))) (if byte-compile-delete-errors form - (funcall (cdr (symbol-function 'the)) type form))))) + (funcall (cdr (symbol-function 'the)) type form)))) + (return-from . + ,#'(lambda (name &optional result) `(return-from-1 ',name ,result))) + (block . + ,#'(lambda (name &rest body) `(block-1 ',name ,＠body)))) "The default macro-environment passed to macroexpand by the compiler. Placing a macro here will cause a macro to have different semantics when expanded by the compiler as when expanded by the interpreter.") ＠＠ -4182,6 +4186,8 ＠＠ ;;; other tricky macro-like special-operators (byte-defop-compiler-1 catch) +(byte-defop-compiler-1 block-1) +(byte-defop-compiler-1 return-from-1) (byte-defop-compiler-1 unwind-protect) (byte-defop-compiler-1 condition-case) (byte-defop-compiler-1 save-excursion) ＠＠ -4196,6 +4202,39 ＠＠ (byte-compile-top-level (cons 'progn (cdr (cdr form))) for-effect)) (byte-compile-out 'byte-catch 0)) +;; `return-from' and `block' are different from `throw' and `catch' when it +;; comes to scope and extent. These differences are implemented for +;; interpreted code in cl-macs.el, in compiled code in bytecomp.el. There's +;; a certain amount of bootstrapping needed for the latter, and until this +;; is done return-from and block behave as throw and catch in their scope +;; and extent. This is only relevant to people working on bytecomp.el. + +(defalias 'return-from-1 'throw) +(defalias 'block-1 'catch) + +(defvar byte-compile-active-blocks nil) + +(defun byte-compile-block-1 (form) + (let* ((name (nth 1 (nth 1 form))) + (elt (list name (copy-symbol name) nil)) + (byte-compile-active-blocks (cons elt byte-compile-active-blocks)) + (body (byte-compile-top-level (cons 'progn (cddr form))))) + (if (nth 2 elt) + (byte-compile-catch `(catch ',(nth 1 elt) ,body)) + (byte-compile-form body)))) + +(defun byte-compile-return-from-1 (form) + (let* ((name (nth 1 (nth 1 form))) + (assq (assq name byte-compile-active-blocks))) + (if assq + (setf (nth 2 assq) t) + (byte-compile-warn + "return-from: %S: no current lexical block with this name" + name)) + (byte-compile-throw + `(throw ',(or (nth 1 assq) (copy-symbol name)) + ,＠(nthcdr 2 form))))) + (defun byte-compile-unwind-protect (form) (byte-compile-push-constant (byte-compile-top-level-body (cdr (cdr form)) t)) diff -r cc7d0e19173c -r 38e24b8be4ea lisp/cl-extra.el --- a/lisp/cl-extra.el Mon Feb 07 00:03:41 2011 +0000 +++ b/lisp/cl-extra.el Mon Feb 07 12:01:24 2011 +0000 ＠＠ -658,8 +658,11 ＠＠ '((quote --cl-rest--))))))) (list (car form) (list* 'lambda (cadadr form) body)))) (let ((found (assq (cadr form) env))) - ;; XEmacs: cadr/caddr operate on nil without errors - (if (eq (cadr (caddr found)) 'cl-labels-args) + ;; XEmacs: cadr/caddr operate on nil without errors. But the + ;; macro definition may be compiled, in which case there's + ;; nothing for us to do. + (if (and (listp (cdr found)) + (eq (cadr (caddr found)) 'cl-labels-args)) (cl-macroexpand-all (cadr (caddr (cadddr found))) env) form)))) ((memq (car form) '(defun defmacro)) diff -r cc7d0e19173c -r 38e24b8be4ea lisp/cl-macs.el --- a/lisp/cl-macs.el Mon Feb 07 00:03:41 2011 +0000 +++ b/lisp/cl-macs.el Mon Feb 07 12:01:24 2011 +0000 ＠＠ -732,6 +732,7 ＠＠ ;;; Blocks and exits. +(defvar cl-active-block-names nil) ;;;###autoload (defmacro block (name &rest body) ＠＠ -741,46 +742,19 ＠＠ in two respects: First, the NAME is an unevaluated symbol rather than a quoted symbol or other form; and second, NAME is lexically rather than dynamically scoped: Only references to it within BODY will work. These -references may appear inside macro expansions, but not inside functions -called from BODY." - (if (cl-safe-expr-p (cons 'progn body)) (cons 'progn body) - (list 'cl-block-wrapper - (list* 'catch (list 'quote (intern (concat "--cl-block-" - (symbol-name name) "--"))) - body)))) - -(defvar cl-active-block-names nil) - -(put 'cl-block-wrapper 'byte-compile - #'(lambda (cl-form) - (if (/= (length cl-form) 2) - (byte-compile-warn-wrong-args cl-form 1)) - - (if (fboundp 'byte-compile-form-do-effect) ; Check for optimizing - ; compiler - (progn - (let* ((cl-entry (cons (nth 1 (nth 1 (nth 1 cl-form))) nil)) - (cl-active-block-names (cons cl-entry - cl-active-block-names)) - (cl-body (byte-compile-top-level - (cons 'progn (cddr (nth 1 cl-form)))))) - (if (cdr cl-entry) - (byte-compile-form (list 'catch (nth 1 (nth 1 cl-form)) - cl-body)) - (byte-compile-form cl-body)))) - (byte-compile-form (nth 1 cl-form))))) - -(put 'cl-block-throw 'byte-compile - #'(lambda (cl-form) - (let ((cl-found (assq (nth 1 (nth 1 cl-form)) cl-active-block-names))) - (if cl-found (setcdr cl-found t))) - (byte-compile-throw (cons 'throw (cdr cl-form))))) +references may appear inside macro expansions and in lambda expressions, but +not inside other functions called from BODY." + (let ((cl-active-block-names (acons name (copy-symbol name) + cl-active-block-names)) + (body (cons 'progn body))) + `(catch ',(cdar cl-active-block-names) + ,(cl-macroexpand-all body cl-macro-environment)))) ;;;###autoload (defmacro return (&optional result) "Return from the block named nil. This is equivalent to `(return-from nil RESULT)'." - (list 'return-from nil result)) + `(return-from nil ,result)) ;;;###autoload (defmacro return-from (name &optional result) ＠＠ -789,9 +763,8 ＠＠ returning RESULT from that form (or nil if RESULT is omitted). This is compatible with Common Lisp, but note that `defun' and `defmacro' do not create implicit blocks as they do in Common Lisp." - (let ((name2 (intern (concat "--cl-block-" (symbol-name name) "--")))) - (list 'cl-block-throw (list 'quote name2) result))) - + `(throw ',(or (cdr (assq name cl-active-block-names)) (copy-symbol name)) + ,result)) ;;; The "loop" macro. diff -r cc7d0e19173c -r 38e24b8be4ea lisp/cl.el --- a/lisp/cl.el Mon Feb 07 00:03:41 2011 +0000 +++ b/lisp/cl.el Mon Feb 07 12:01:24 2011 +0000 ＠＠ -205,19 +205,6 ＠＠ (defalias 'cl-map-extents 'map-extents) -;;; Blocks and exits. - -;; This used to be #'identity, but that didn't preserve multiple values in -;; interpreted code. #'and isn't great either, there's no error on too many -;; arguments passed to it when interpreted. Fortunately most of the places -;; where cl-block-wrapper is called are generated from old, established -;; macros, so too many arguments resulting from human error is unlikely; and -;; the byte compile handler in cl-macs.el warns if more than one arg is -;; passed to it. -(defalias 'cl-block-wrapper 'and) - -(defalias 'cl-block-throw 'throw) - ;;; XEmacs; multiple values are in eval.c and cl-macs.el. ;;; We no longer support `multiple-value-apply', which was ill-conceived to diff -r cc7d0e19173c -r 38e24b8be4ea tests/ChangeLog --- a/tests/ChangeLog Mon Feb 07 00:03:41 2011 +0000 +++ b/tests/ChangeLog Mon Feb 07 12:01:24 2011 +0000 ＠＠ -1,3 +1,10 ＠＠ +2011-02-07 Aidan Kehoe <kehoea(a)parhasard.net&gt; + + * automated/lisp-tests.el: + Test lexical scope for `block', `return-from'; add a + Known-Bug-Expect-Failure for a contorted example that fails when + byte-compiled. + 2011-01-23 Aidan Kehoe <kehoea(a)parhasard.net&gt; * automated/lisp-tests.el: diff -r cc7d0e19173c -r 38e24b8be4ea tests/automated/lisp-tests.el --- a/tests/automated/lisp-tests.el Mon Feb 07 00:03:41 2011 +0000 +++ b/tests/automated/lisp-tests.el Mon Feb 07 12:01:24 2011 +0000 ＠＠ -2871,4 +2871,33 ＠＠ (subseq bit-vector 0 4) (append (subseq bit-vector 4) nil))))) +;;----------------------------------------------------- +;; Test `block', `return-from' +;;----------------------------------------------------- +(Assert (eql 1 (block outer + (flet ((outtahere (n) (return-from outer n))) + (block outer (outtahere 1))) + 2)) + "checking `block' and `return-from' are lexically scoped correctly") + +;; Other tests are available in Paul Dietz' test suite, and pass. The above, +;; which we used to fail, is based on a test in the Hyperspec. We still +;; behave incorrectly when compiled for the contorted-example function of +;; CLTL2, whence the following test: + +(flet ((needs-lexical-context (first second third) + (if (eql 0 first) + (funcall second) + (block awkward + (+ 5 (needs-lexical-context + (1- first) + third + #'(lambda () (return-from awkward 0))) + first))))) + (if (compiled-function-p (symbol-function 'needs-lexical-context)) + (Known-Bug-Expect-Failure + (Assert (eql 0 (needs-lexical-context 2 nil nil)) + "the function special operator doesn't create a lexical context.")) + (Assert (eql 0 (needs-lexical-context 2 nil nil))))) + ;;; end of lisp-tests.el -- “Apart from the nine-banded armadillo, man is the only natural host of Mycobacterium leprae, although it can be grown in the footpads of mice.” -- Kumar & Clark, Clinical Medicine, summarising improbable leprosy research _______________________________________________ XEmacs-Patches mailing list XEmacs-Patches(a)xemacs.org http://lists.xemacs.org/mailman/listinfo/xemacs-patches