bug#15166: 24.3.50; Isearch for an octal code

[Juri Linkov]

BTW, while looking at `isearch-quote-char' I noticed that it
requires a comment saying that `C-q SPC' is an obsolete feature
(that is now replaced by `M-s SPC').  Then it should be also
de-documented in the docstring of `isearch-forward-regexp':

=== modified file 'lisp/isearch.el'
--- lisp/isearch.el     2013-07-05 20:15:32 +0000
+++ lisp/isearch.el     2013-08-23 22:42:25 +0000
@@ -823,7 +823,6 @@ (defun isearch-forward-regexp (&optional
 
 In incremental searches, a space or spaces normally matches any
 whitespace defined by the variable `search-whitespace-regexp'.
-To search for a literal space and nothing else, enter C-q SPC.
 To toggle whitespace matching, use `isearch-toggle-lax-whitespace'."
   (interactive "P\np")
   (isearch-mode t (null not-regexp) nil (not no-recursive-edit)))
@@ -2730,6 +2748,8 @@ (defun isearch-quote-char (&optional cou
     ;; single-byte character set, and convert them to Emacs
     ;; characters.
     (if (and isearch-regexp isearch-regexp-lax-whitespace (= char ?\s))
+       ;; Obsolete feature: to search for a literal space
+       ;; and nothing else, enter C-q SPC.
        (if (subregexp-context-p isearch-string (length isearch-string))
            (isearch-process-search-string "[ ]" " ")
          (isearch-process-search-char char count))