From: Shigeru Fukaya <shigeru.fukaya@gmail.com>
Date: Wed, 18 Dec 2013 04:46:49 +0000 (+0800)
Subject: apropos.el (apropos-words-to-regexp): Fix algorithm.
X-Git-Tag: emacs-24.3.90~173^2^2~42^2~45^2~387^2~352
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=ba874b6430893be55d48840a901aac4e64a4befc;p=emacs.git

apropos.el (apropos-words-to-regexp): Fix algorithm.

* apropos.el (apropos-words-to-regexp): Fix algorithm.

Fixes: debbugs:13946
---

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 96410c6c929..fa79352e7a2 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,7 @@
+2013-12-18  Shigeru Fukaya <shigeru.fukaya@gmail.com>
+
+	* apropos.el (apropos-words-to-regexp): Fix algorithm (Bug#13946).
+
 2013-12-18  Glenn Morris  <rgm@gnu.org>
 
 	* Makefile.in (BYTE_COMPILE_FLAGS): Set load-prefer-newer to t.
diff --git a/lisp/apropos.el b/lisp/apropos.el
index 7a1a6f6a75a..b7c5aaddcb1 100644
--- a/lisp/apropos.el
+++ b/lisp/apropos.el
@@ -341,16 +341,21 @@ before finding a label."
 
 
 (defun apropos-words-to-regexp (words wild)
-  "Make regexp matching any two of the words in WORDS."
-  (concat "\\("
-	  (mapconcat 'identity words "\\|")
-	  "\\)"
-	  (if (cdr words)
-	      (concat wild
-		      "\\("
-		      (mapconcat 'identity words "\\|")
-		      "\\)")
-	    "")))
+  "Make regexp matching any two of the words in WORDS.
+WILD should be a subexpression matching wildcards between matches."
+  (setq words (delete-dups (copy-sequence words)))
+  (if (null (cdr words))
+      (car words)
+    (mapconcat
+     (lambda (w)
+       (concat "\\(?:" w "\\)" ;; parens for synonyms
+               wild "\\(?:"
+               (mapconcat 'identity
+			  (delq w (copy-sequence words))
+			  "\\|")
+               "\\)"))
+     words
+     "\\|")))
 
 ;;;###autoload
 (defun apropos-read-pattern (subject)