From 8c296cae6e0363485b1f24b76e7fb06984f3117e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Mattias=20Engdeg=C3=A5rd?= Date: Tue, 14 May 2019 11:43:49 +0200 Subject: [PATCH] Use faster unmatchable regexp The unmatchable regexp a\` used in many places is unnecessarily slow in searching (unanchored) matches; replace it with the faster \`a\` as suggested by Philippe Schnoebelen. * lisp/emacs-lisp/regexp-opt.el (regexp-opt) * lisp/progmodes/cc-defs.el (cc-conditional-require-after-load) (c-make-keywords-re) * lisp/progmodes/cc-engine.el (c-beginning-of-statement-1) (c-forward-<>-arglist-recur, c-forward-decl-or-cast-1) (c-looking-at-decl-block) * lisp/progmodes/cc-fonts.el (c-doc-line-join-re) (c-doc-bright-comment-start-re) * lisp/progmodes/cc-langs.el (c-populate-syntax-table) (c-assignment-op-regexp) (c-block-comment-ender-regexp, c-font-lock-comment-end-skip) (c-block-comment-start-regexp, c-line-comment-start-regexp) (c-doc-comment-start-regexp, c-decl-start-colon-kwd-re) (c-type-decl-prefix-key, c-type-decl-operator-prefix-key) (c-pre-id-bracelist-key, c-enum-clause-introduction-re) (c-nonlabel-token-2-key) * lisp/progmodes/cc-mode.el (c-doc-fl-decl-start, c-doc-fl-decl-end) * lisp/progmodes/cc-vars.el (c-noise-macro-with-parens-name-re) (c-noise-macro-name-re, c-make-noise-macro-regexps) * lisp/progmodes/octave.el (octave-help-mode): Use faster unmatchable regexp. * lisp/textmodes/ispell.el (ispell-non-empty-string): Fix broken 'unmatchable' regexp. --- lisp/emacs-lisp/regexp-opt.el | 4 ++-- lisp/progmodes/cc-defs.el | 6 +++--- lisp/progmodes/cc-engine.el | 8 ++++---- lisp/progmodes/cc-fonts.el | 4 ++-- lisp/progmodes/cc-langs.el | 26 +++++++++++++------------- lisp/progmodes/cc-mode.el | 4 ++-- lisp/progmodes/cc-vars.el | 8 ++++---- lisp/progmodes/octave.el | 2 +- lisp/textmodes/ispell.el | 2 +- 9 files changed, 32 insertions(+), 32 deletions(-) diff --git a/lisp/emacs-lisp/regexp-opt.el b/lisp/emacs-lisp/regexp-opt.el index d883752d71..220a4bfa7a 100644 --- a/lisp/emacs-lisp/regexp-opt.el +++ b/lisp/emacs-lisp/regexp-opt.el @@ -144,9 +144,9 @@ regexp-opt (sort (copy-sequence strings) 'string-lessp))) (re (cond - ;; No strings: return a\` which cannot match anything. + ;; No strings: return \`a\` which cannot match anything. ((null strings) - (concat (or open "\\(?:") "a\\`\\)")) + (concat (or open "\\(?:") "\\`a\\`\\)")) ;; If we cannot reorder, give up all attempts at ;; optimisation. There is room for improvement (Bug#34641). ((and keep-order (regexp-opt--contains-prefix sorted-strings)) diff --git a/lisp/progmodes/cc-defs.el b/lisp/progmodes/cc-defs.el index cd4ed6b352..1ae328d4ff 100644 --- a/lisp/progmodes/cc-defs.el +++ b/lisp/progmodes/cc-defs.el @@ -81,7 +81,7 @@ (progn (require 'font-lock) (let (font-lock-keywords) - (font-lock-compile-keywords '("a\\`")) ; doesn't match anything. + (font-lock-compile-keywords '("\\`a\\`")) ; doesn't match anything. font-lock-keywords)))) @@ -1890,8 +1890,8 @@ c-make-keywords-re ;; Produce a regexp that doesn't match anything. (if adorn - "\\(a\\`\\)" - "a\\`"))) + "\\(\\`a\\`\\)" + "\\`a\\`"))) (put 'c-make-keywords-re 'lisp-indent-function 1) diff --git a/lisp/progmodes/cc-engine.el b/lisp/progmodes/cc-engine.el index a25d059553..648e7197f3 100644 --- a/lisp/progmodes/cc-engine.el +++ b/lisp/progmodes/cc-engine.el @@ -907,7 +907,7 @@ c-beginning-of-statement-1 stack ;; Regexp which matches "for", "if", etc. (cond-key (or c-opt-block-stmt-key - "a\\`")) ; Doesn't match anything. + "\\`a\\`")) ; Doesn't match anything. ;; Return value. (ret 'same) ;; Positions of the last three sexps or bounds we've stopped at. @@ -7638,7 +7638,7 @@ c-forward-<>-arglist-recur (progn (c-forward-syntactic-ws) (when (or (and c-record-type-identifiers all-types) - (not (equal c-inside-<>-type-key "\\(a\\`\\)"))) + (not (equal c-inside-<>-type-key "\\(\\`a\\`\\)"))) (c-forward-syntactic-ws) (cond ((eq (char-after) ??) @@ -9245,7 +9245,7 @@ c-forward-decl-or-cast-1 ;; Skip over type decl prefix operators. (Note similar code in ;; `c-forward-declarator'.) (if (and c-recognize-typeless-decls - (equal c-type-decl-prefix-key "a\\`")) ; Regexp which doesn't match + (equal c-type-decl-prefix-key "\\`a\\`")) ; Regexp which doesn't match (when (eq (char-after) ?\() (progn (setq paren-depth (1+ paren-depth)) @@ -10878,7 +10878,7 @@ c-looking-at-decl-block ;; legal because it's part of a "compound keyword" like ;; "enum class". Of course, if c-after-brace-list-key ;; is nil, we can skip the test. - (or (equal c-after-brace-list-key "a\\`") ; Regexp which doesn't match + (or (equal c-after-brace-list-key "\\`a\\`") ; Regexp which doesn't match (save-match-data (save-excursion (not diff --git a/lisp/progmodes/cc-fonts.el b/lisp/progmodes/cc-fonts.el index 5f09be60a6..bed9259e42 100644 --- a/lisp/progmodes/cc-fonts.el +++ b/lisp/progmodes/cc-fonts.el @@ -2580,14 +2580,14 @@ pike-font-lock-keywords ;;; Doc comments. -(defvar c-doc-line-join-re "a\\`") +(defvar c-doc-line-join-re "\\`a\\`") ;; Matches a join of two lines in a doc comment. ;; This should not be changed directly, but instead set by ;; `c-setup-doc-comment-style'. This variable is used in `c-find-decl-spots' ;; in (e.g.) autodoc style comments to bridge the gap between a "@\n" at an ;; EOL and the token following "//!" on the next line. -(defvar c-doc-bright-comment-start-re "a\\`") +(defvar c-doc-bright-comment-start-re "\\`a\\`") ;; Matches the start of a "bright" comment, one whose contents may be ;; fontified by, e.g., `c-font-lock-declarations'. diff --git a/lisp/progmodes/cc-langs.el b/lisp/progmodes/cc-langs.el index 8b7e4ef7c0..6fdcd6cfc7 100644 --- a/lisp/progmodes/cc-langs.el +++ b/lisp/progmodes/cc-langs.el @@ -945,7 +945,7 @@ c-populate-syntax-table (c-make-keywords-re 'appendable (c-lang-const c-cpp-include-directives)) "[ \t]*") - "a\\`")) ; Doesn't match anything + "\\`a\\`")) ; Doesn't match anything (c-lang-defvar c-cpp-include-key (c-lang-const c-cpp-include-key)) (c-lang-defconst c-opt-cpp-macro-define @@ -1331,7 +1331,7 @@ 'c-opt-op-identitier-prefix (c--set-difference (c-lang-const c-assignment-operators) '("=") :test 'string-equal))) - "a\\`")) ; Doesn't match anything. + "\\`a\\`")) ; Doesn't match anything. (c-lang-defvar c-assignment-op-regexp (c-lang-const c-assignment-op-regexp)) @@ -1554,7 +1554,7 @@ 'c-opt-op-identitier-prefix ;; language) t (if (c-lang-const c-block-comment-ender) (regexp-quote (c-lang-const c-block-comment-ender)) - "a\\`")) ; Doesn't match anything. + "\\`a\\`")) ; Doesn't match anything. (c-lang-defvar c-block-comment-ender-regexp (c-lang-const c-block-comment-ender-regexp)) @@ -1565,7 +1565,7 @@ 'c-opt-op-identitier-prefix ;; `font-lock-comment-delimiter-face'. t (if (c-lang-const c-block-comment-ender) (concat "[ \t]*" (c-lang-const c-block-comment-ender-regexp)) - "a\\`")) ; Doesn't match anything. + "\\`a\\`")) ; Doesn't match anything. (c-lang-setvar font-lock-comment-end-skip (c-lang-const c-font-lock-comment-end-skip)) @@ -1584,7 +1584,7 @@ 'c-opt-op-identitier-prefix ;; language) t (if (c-lang-const c-block-comment-starter) (regexp-quote (c-lang-const c-block-comment-starter)) - "a\\`")) ; Doesn't match anything. + "\\`a\\`")) ; Doesn't match anything. (c-lang-defvar c-block-comment-start-regexp (c-lang-const c-block-comment-start-regexp)) @@ -1593,7 +1593,7 @@ 'c-opt-op-identitier-prefix ;; language; it does in all 7 CC Mode languages). t (if (c-lang-const c-line-comment-starter) (regexp-quote (c-lang-const c-line-comment-starter)) - "a\\`")) ; Doesn't match anything. + "\\`a\\`")) ; Doesn't match anything. (c-lang-defvar c-line-comment-start-regexp (c-lang-const c-line-comment-start-regexp)) @@ -1628,7 +1628,7 @@ 'c-opt-op-identitier-prefix (c-lang-defconst c-doc-comment-start-regexp "Regexp to match the start of documentation comments." - t "a\\`" ; Doesn't match anything. + t "\\`a\\`" ; Doesn't match anything. ;; From font-lock.el: `doxygen' uses /*! while others use /**. (c c++ objc) "/\\*[*!]" java "/\\*\\*" @@ -3112,7 +3112,7 @@ 'c-opt-op-identitier-prefix "Regexp matching a keyword that is followed by a colon, where the whole construct can precede a declaration. E.g. \"public:\" in C++." - t "a\\`" ; Doesn't match anything. + t "\\`a\\`" ; Doesn't match anything. c++ (c-make-keywords-re t (c-lang-const c-protection-kwds))) (c-lang-defvar c-decl-start-colon-kwd-re (c-lang-const c-decl-start-colon-kwd-re)) @@ -3309,7 +3309,7 @@ 'c-opt-op-identitier-prefix t (if (c-lang-const c-type-modifier-kwds) (concat (regexp-opt (c-lang-const c-type-modifier-kwds) t) "\\>") ;; Default to a regexp that never matches. - "a\\`") + "\\`a\\`") ;; Check that there's no "=" afterwards to avoid matching tokens ;; like "*=". (c objc) (concat "\\(" @@ -3347,7 +3347,7 @@ 'c-opt-op-identitier-prefix as the end of the operator. Identifier syntax is in effect when this is matched \(see `c-identifier-syntax-table')." t ;; Default to a regexp that never matches. - "a\\`" + "\\`a\\`" ;; Check that there's no "=" afterwards to avoid matching tokens ;; like "*=". (c objc) (concat "\\(\\*\\)" @@ -3506,7 +3506,7 @@ 'c-opt-op-identitier-prefix (c-lang-defconst c-pre-id-bracelist-key "A regexp matching tokens which, preceding an identifier, signify a bracelist. " - t "a\\`" ; Doesn't match anything. + t "\\`a\\`" ; Doesn't match anything. c++ "new\\([^[:alnum:]_$]\\|$\\)\\|&&?\\(\\S.\\|$\\)") (c-lang-defvar c-pre-id-bracelist-key (c-lang-const c-pre-id-bracelist-key)) @@ -3562,7 +3562,7 @@ 'c-opt-op-identitier-prefix ;; before the '{' of the enum list, to avoid searching too far. "[^][{};/#=]*" "{") - "a\\`")) ; Doesn't match anything. + "\\`a\\`")) ; Doesn't match anything. (c-lang-defvar c-enum-clause-introduction-re (c-lang-const c-enum-clause-introduction-re)) @@ -3678,7 +3678,7 @@ 'c-opt-op-identitier-prefix "Regexp matching things that can't occur two symbols before a colon in a label construct. This catches C++'s inheritance construct \"class foo : bar\". Only used if `c-recognize-colon-labels' is set." - t "a\\`" ; Doesn't match anything. + t "\\`a\\`" ; Doesn't match anything. c++ (c-make-keywords-re t '("class"))) (c-lang-defvar c-nonlabel-token-2-key (c-lang-const c-nonlabel-token-2-key)) diff --git a/lisp/progmodes/cc-mode.el b/lisp/progmodes/cc-mode.el index bd62fc754a..57cfdb96b3 100644 --- a/lisp/progmodes/cc-mode.el +++ b/lisp/progmodes/cc-mode.el @@ -1825,7 +1825,7 @@ c-doc-fl-decl-start ;; by `c-doc-line-join-re'), return the position of the first line of the ;; sequence. Otherwise, return nil. Point has no significance at entry to ;; and exit from this function. - (when (not (equal c-doc-line-join-re "a\\`")) + (when (not (equal c-doc-line-join-re "\\`a\\`")) (goto-char pos) (back-to-indentation) (and (or (looking-at c-comment-start-regexp) @@ -1842,7 +1842,7 @@ c-doc-fl-decl-end ;; marker (as defined by `c-doc-line-join-re), return the position of ;; the BOL at the end of the sequence. Otherwise, return nil. Point has no ;; significance at entry to and exit from this function. - (when (not (equal c-doc-line-join-re "a\\`")) + (when (not (equal c-doc-line-join-re "\\`a\\`")) (goto-char pos) (back-to-indentation) (let ((here (point))) diff --git a/lisp/progmodes/cc-vars.el b/lisp/progmodes/cc-vars.el index 6e8acd4c0d..3b30d18872 100644 --- a/lisp/progmodes/cc-vars.el +++ b/lisp/progmodes/cc-vars.el @@ -1648,9 +1648,9 @@ c-asymmetry-fontification-flag :group 'c) ;; Initialize the next two to a regexp which never matches. -(defvar c-noise-macro-with-parens-name-re "a\\`") +(defvar c-noise-macro-with-parens-name-re "\\`a\\`") (make-variable-buffer-local 'c-noise-macro-with-parens-name-re) -(defvar c-noise-macro-name-re "a\\`") +(defvar c-noise-macro-name-re "\\`a\\`") (make-variable-buffer-local 'c-noise-macro-name-re) (defcustom c-noise-macro-names nil @@ -1682,7 +1682,7 @@ c-make-noise-macro-regexps ;; Convert `c-noise-macro-names' and `c-noise-macro-with-parens-names' into ;; `c-noise-macro-name-re' and `c-noise-macro-with-parens-name-re'. (setq c-noise-macro-with-parens-name-re - (cond ((null c-noise-macro-with-parens-names) "a\\`") ; Never matches. + (cond ((null c-noise-macro-with-parens-names) "\\`a\\`") ;Never matches. ((consp c-noise-macro-with-parens-names) (concat (regexp-opt c-noise-macro-with-parens-names t) "\\([^[:alnum:]_$]\\|$\\)")) @@ -1691,7 +1691,7 @@ c-make-noise-macro-regexps (t (error "c-make-noise-macro-regexps: \ c-noise-macro-with-parens-names is invalid: %s" c-noise-macro-with-parens-names)))) (setq c-noise-macro-name-re - (cond ((null c-noise-macro-names) "a\\`") ; Never matches anything. + (cond ((null c-noise-macro-names) "\\`a\\`") ; Never matches anything. ((consp c-noise-macro-names) (concat (regexp-opt c-noise-macro-names t) "\\([^[:alnum:]_$]\\|$\\)")) diff --git a/lisp/progmodes/octave.el b/lisp/progmodes/octave.el index 52e5fd477f..96058bca14 100644 --- a/lisp/progmodes/octave.el +++ b/lisp/progmodes/octave.el @@ -1691,7 +1691,7 @@ octave-help-mode (eval-and-compile (require 'help-mode)) ;; Don't highlight `EXAMPLE' as elisp symbols by using a regexp that ;; can never match. - (setq-local help-xref-symbol-regexp "x\\`")) + (setq-local help-xref-symbol-regexp "\\`x\\`")) (defun octave-help (fn) "Display the documentation of FN." diff --git a/lisp/textmodes/ispell.el b/lisp/textmodes/ispell.el index 6553a2799b..49698dd120 100644 --- a/lisp/textmodes/ispell.el +++ b/lisp/textmodes/ispell.el @@ -4016,7 +4016,7 @@ ispell-message (defun ispell-non-empty-string (string) (if (or (not string) (string-equal string "")) - "\\'\\`" ; An unmatchable string if string is null. + "\\`a\\`" ; An unmatchable string if string is null. (regexp-quote string))) -- 2.20.1