Merge from emacs-24; up to 2014-06-08T18:27:22Z!eggert@cs.ucla.edu

[bpt/emacs.git] / lisp / emacs-lisp / regexp-opt.el

diff --git a/lisp/emacs-lisp/regexp-opt.el b/lisp/emacs-lisp/regexp-opt.el
index ac391fe..ff93881 100644 (file)
--- a/lisp/emacs-lisp/regexp-opt.el
+++ b/lisp/emacs-lisp/regexp-opt.el
@@ -1,9 +1,9 @@
 ;;; regexp-opt.el --- generate efficient regexps to match strings
 
-;; Copyright (C) 1994-2012 Free Software Foundation, Inc.
+;; Copyright (C) 1994-2014 Free Software Foundation, Inc.
 
 ;; Author: Simon Marshall <simon@gnu.org>
-;; Maintainer: FSF
+;; Maintainer: emacs-devel@gnu.org
 ;; Keywords: strings, regexps, extensions
 
 ;; This file is part of GNU Emacs.
@@ -136,14 +136,11 @@ This means the number of non-shy regexp grouping constructs
 \f
 ;;; Workhorse functions.
 
-(eval-when-compile
-  (require 'cl))
-
 (defun regexp-opt-group (strings &optional paren lax)
   "Return a regexp to match a string in the sorted list STRINGS.
 If PAREN non-nil, output regexp parentheses around returned regexp.
 If LAX non-nil, don't output parentheses if it doesn't require them.
-Merges keywords to avoid backtracking in Emacs' regexp matcher."
+Merges keywords to avoid backtracking in Emacs's regexp matcher."
   ;; The basic idea is to find the shortest common prefix or suffix, remove it
   ;; and recurse.  If there is no prefix, we divide the list into two so that
   ;; \(at least) one half will have at least a one-character common prefix.
@@ -208,9 +205,7 @@ Merges keywords to avoid backtracking in Emacs' regexp matcher."
                      (regexp-opt-group suffixes t t)
                      close-group))
 
-         (let* ((sgnirts (mapcar (lambda (s)
-                                   (concat (nreverse (string-to-list s))))
-                                 strings))
+         (let* ((sgnirts (mapcar #'reverse strings))
                 (xiffus (try-completion "" sgnirts)))
            (if (> (length xiffus) 0)
                ;; common suffix: take it and recurse on the prefixes.
@@ -221,8 +216,7 @@ Merges keywords to avoid backtracking in Emacs' regexp matcher."
                              'string-lessp)))
                  (concat open-group
                          (regexp-opt-group prefixes t t)
-                         (regexp-quote
-                          (concat (nreverse (string-to-list xiffus))))
+                         (regexp-quote (nreverse xiffus))
                          close-group))
 
              ;; Otherwise, divide the list into those that start with a
@@ -237,7 +231,8 @@ Merges keywords to avoid backtracking in Emacs' regexp matcher."
 
 
 (defun regexp-opt-charset (chars)
-  "Return a regexp to match a character in CHARS."
+  "Return a regexp to match a character in CHARS.
+CHARS should be a list of characters."
   ;; The basic idea is to find character ranges.  Also we take care in the
   ;; position of character set meta characters in the character set regexp.
   ;;
@@ -248,15 +243,15 @@ Merges keywords to avoid backtracking in Emacs' regexp matcher."
     ;;
     ;; Make a character map but extract character set meta characters.
     (dolist (char chars)
-      (case char
-       (?\]
-        (setq bracket "]"))
-       (?^
-        (setq caret "^"))
-       (?-
-        (setq dash "-"))
-       (otherwise
-        (aset charmap char t))))
+      (cond
+       ((eq char ?\])
+       (setq bracket "]"))
+       ((eq char ?^)
+       (setq caret "^"))
+       ((eq char ?-)
+       (setq dash "-"))
+       (t
+       (aset charmap char t))))
     ;;
     ;; Make a character set from the map using ranges where applicable.
     (map-char-table
@@ -268,14 +263,14 @@ Merges keywords to avoid backtracking in Emacs' regexp matcher."
                   (setq charset (format "%s%c-%c" charset start end))
                 (while (>= end start)
                   (setq charset (format "%s%c" charset start))
-                  (incf start)))
+                  (setq start (1+ start))))
               (setq start (car c) end (cdr c)))
           (if (= (1- c) end) (setq end c)
             (if (> end (+ start 2))
               (setq charset (format "%s%c-%c" charset start end))
             (while (>= end start)
               (setq charset (format "%s%c" charset start))
-              (incf start)))
+              (setq start (1+ start))))
             (setq start c end c)))))
      charmap)
     (when (>= end start)
@@ -283,11 +278,13 @@ Merges keywords to avoid backtracking in Emacs' regexp matcher."
          (setq charset (format "%s%c-%c" charset start end))
        (while (>= end start)
          (setq charset (format "%s%c" charset start))
-         (incf start))))
+         (setq start (1+ start)))))
     ;;
     ;; Make sure a caret is not first and a dash is first or last.
     (if (and (string-equal charset "") (string-equal bracket ""))
-       (concat "[" dash caret "]")
+       (if (string-equal dash "")
+            "\\^"                       ; [^] is not a valid regexp
+          (concat "[" dash caret "]"))
       (concat "[" bracket charset caret dash "]"))))
 
 (provide 'regexp-opt)