Improve previous interpreter-mode-alist change

* lisp/files.el (interpreter-mode-alist): Remove \\` \\' parts.
(set-auto-mode): Don't regexp-quote elements.

* lisp/progmodes/python.el (interpreter-mode-alist): Remove \\` \\'.

* lisp/progmodes/cc-mode.el (interpreter-mode-alist):
* lisp/progmodes/ruby-mode.el (interpreter-mode-alist):
Revert previous change.

* etc/NEWS: Update.

6 files changed, 47 insertions, 47 deletions

diff --git a/etc/NEWS b/etc/NEWS
index 929c86a7ba6..a5da8eaa893 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -616,11 +616,9 @@ Formerly it returned a list (-1 LOW USEC PSEC), but this was ambiguous
 in the presence of files with negative time stamps.
 
 ** The cars of the elements in `interpreter-mode-alist' are now treated
-as regexps rather than literal strings.  For the time being, any
-element whose car does not start with "\\" is still treated as a
-literal string, so this change should not cause any incompatibilities
-if you have code that just adds elements to the list, only if you are
-actually using interpreter-mode-alist for something.
+as regexps rather than literal strings.  Technically this is an
+incompatible change, but unless you are using interpreter-mode-alist
+for something (not just adding elements to it), it ought not to affect you.
 
 
 * Lisp Changes in Emacs 24.4
diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index e1f1aaa1888..89610870f10 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,12 @@
+2013-09-11  Glenn Morris  <rgm@gnu.org>
+
+        * files.el (interpreter-mode-alist): Remove \\` \\' parts.
+        (set-auto-mode): Don't regexp-quote elements.
+        * progmodes/python.el (interpreter-mode-alist): Remove \\` \\'.
+        * progmodes/cc-mode.el (interpreter-mode-alist):
+        * progmodes/ruby-mode.el (interpreter-mode-alist):
+        Revert previous change.
+
 2013-09-11  Stefan Monnier  <monnier@iro.umontreal.ca>
 
         * play/snake.el (snake-mode):
diff --git a/lisp/files.el b/lisp/files.el
index 2315448c549..5d8fbda6154 100644
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -2447,43 +2447,34 @@ and `magic-mode-alist', which determines modes based on file contents.")
   (mapcar
    (lambda (l)
      (cons (purecopy (car l)) (cdr l)))
-   '(("\\`\\(mini\\)?perl5?\\'" . perl-mode)
-     ("\\`wishx?\\'" . tcl-mode)
-     ("\\`tcl\\(sh\\)?\\'" . tcl-mode)
-     ("\\`expect\\'" . tcl-mode)
-     ("\\`scm\\'" . scheme-mode)
-     ("\\`[acjkwz]sh\\'" . sh-mode)
-     ("\\`bash2?\\'" . sh-mode)
-     ("\\`dtksh\\'" . sh-mode)
-     ("\\`es\\'" . sh-mode)
-     ("\\`itcsh\\'" . sh-mode)
-     ("\\`oash\\'" . sh-mode)
-     ("\\`pdksh\\'" . sh-mode)
-     ("\\`rbash\\'" . sh-mode)
-     ("\\`rc\\'" . sh-mode)
-     ("\\`rpm\\'" . sh-mode)
-     ("\\`sh5?\\'" . sh-mode)
-     ("\\`tcsh\\'" . sh-mode)
-     ("\\`wksh\\'" . sh-mode)
-     ("\\`tail\\'" . text-mode)
-     ("\\`more\\'" . text-mode)
-     ("\\`less\\'" . text-mode)
-     ("\\`pg\\'" . text-mode)
-     ("\\`make\\'" . makefile-gmake-mode)               ; Debian uses this
-     ("\\`guile\\'" . scheme-mode)
-     ("\\`clisp\\'" . lisp-mode)
-     ("\\`emacs\\'" . emacs-lisp-mode)))
+   '(("\\(mini\\)?perl5?" . perl-mode)
+     ("wishx?" . tcl-mode)
+     ("tcl\\(sh\\)?" . tcl-mode)
+     ("expect" . tcl-mode)
+     ("scm" . scheme-mode)
+     ("[acjkwz]sh" . sh-mode)
+     ("r?bash2?" . sh-mode)
+     ("\\(dt\\|pd\\|w\\)ksh" . sh-mode)
+     ("es" . sh-mode)
+     ("i?tcsh" . sh-mode)
+     ("oash" . sh-mode)
+     ("rc" . sh-mode)
+     ("rpm" . sh-mode)
+     ("sh5?" . sh-mode)
+     ("tail" . text-mode)
+     ("more" . text-mode)
+     ("less" . text-mode)
+     ("pg" . text-mode)
+     ("make" . makefile-gmake-mode)             ; Debian uses this
+     ("guile" . scheme-mode)
+     ("clisp" . lisp-mode)
+     ("emacs" . emacs-lisp-mode)))
   "Alist mapping interpreter names to major modes.
 This is used for files whose first lines match `auto-mode-interpreter-regexp'.
 Each element looks like (REGEXP . MODE).
-If REGEXP matches the name (minus any directory part) of the interpreter
-specified in the first line of a script, enable major mode MODE.
-
-Emacs versions earlier than 24.4 treat the car of each element as a
-literal string that must match the entire name, rather than a regexp.
-For backwards compatibility, any REGEXP that does not begin with \"\\\\\"
-continues to be treated in this way.  This behavior may be removed in
-future and should not be relied upon.
+If \\\\`REGEXP\\\\' matches the name (minus any directory part) of
+the interpreter specified in the first line of a script, enable
+major mode MODE.
 
 See also `auto-mode-alist'.")
 
@@ -2687,13 +2678,11 @@ we don't actually set it to the same mode the buffer already has."
          ;; same time.
          (setq done (assoc-default
                      (file-name-nondirectory mode)
-                     ;; Backwards compat: if car of i-m-alist does not start
-                     ;; with "\\", treat as literal string.
                      (mapcar (lambda (e)
-                               (if (string-match-p "\\`\\\\" (car e))
+                               (if (string-match-p "\\`\\\\`" (car e))
                                    e
                                  (cons
-                                  (format "\\`%s\\'" (regexp-quote (car e)))
+                                  (format "\\`%s\\'" (car e))
                                   (cdr e))))
                              interpreter-mode-alist)
                      #'string-match-p))
diff --git a/lisp/progmodes/cc-mode.el b/lisp/progmodes/cc-mode.el
index bffc5b95d25..e977a415d62 100644
--- a/lisp/progmodes/cc-mode.el
+++ b/lisp/progmodes/cc-mode.el
@@ -1555,7 +1555,7 @@ Key bindings:
                   (cons "Pike" (c-lang-const c-mode-menu pike)))
 
 ;;;###autoload (add-to-list 'auto-mode-alist '("\\.\\(u?lpc\\|pike\\|pmod\\(\\.in\\)?\\)\\'" . pike-mode))
-;;;###autoload (add-to-list 'interpreter-mode-alist '("\\`pike\\'" . pike-mode))
+;;;###autoload (add-to-list 'interpreter-mode-alist '("pike" . pike-mode))
 
 ;;;###autoload
 (define-derived-mode pike-mode prog-mode "Pike"
@@ -1589,7 +1589,10 @@ Key bindings:
 ;; Support for AWK
 
 ;;;###autoload (add-to-list 'auto-mode-alist '("\\.awk\\'" . awk-mode))
-;;;###autoload (add-to-list 'interpreter-mode-alist '("\\`[gmn]?awk\\'" . awk-mode))
+;;;###autoload (add-to-list 'interpreter-mode-alist '("awk" . awk-mode))
+;;;###autoload (add-to-list 'interpreter-mode-alist '("mawk" . awk-mode))
+;;;###autoload (add-to-list 'interpreter-mode-alist '("nawk" . awk-mode))
+;;;###autoload (add-to-list 'interpreter-mode-alist '("gawk" . awk-mode))
 
 (c-define-abbrev-table 'awk-mode-abbrev-table
   '(("else" "else" c-electric-continued-statement 0)
diff --git a/lisp/progmodes/python.el b/lisp/progmodes/python.el
index 5eecc347f03..5f919bf495f 100644
--- a/lisp/progmodes/python.el
+++ b/lisp/progmodes/python.el
@@ -225,7 +225,7 @@
 ;;;###autoload
 (add-to-list 'auto-mode-alist (cons (purecopy "\\.py\\'")  'python-mode))
 ;;;###autoload
-(add-to-list 'interpreter-mode-alist (cons (purecopy "\\`python[0-9.]*\\'") 'python-mode))
+(add-to-list 'interpreter-mode-alist (cons (purecopy "python[0-9.]*") 'python-mode))
 
 (defgroup python nil
   "Python Language's flying circus support for Emacs."
diff --git a/lisp/progmodes/ruby-mode.el b/lisp/progmodes/ruby-mode.el
index 9dc2c4fb6c9..0f868255589 100644
--- a/lisp/progmodes/ruby-mode.el
+++ b/lisp/progmodes/ruby-mode.el
@@ -1968,7 +1968,8 @@ The variable `ruby-indent-level' controls the amount of indentation.
                                      "\\)\\'")) 'ruby-mode))
 
 ;;;###autoload
-(add-to-list 'interpreter-mode-alist (cons (purecopy "\\`\\(rbx\\|j?ruby\\(1\\.[89]\\)?\\)\\'") 'ruby-mode))
+(dolist (name (list "ruby" "rbx" "jruby" "ruby1.9" "ruby1.8"))
+  (add-to-list 'interpreter-mode-alist (cons (purecopy name) 'ruby-mode)))
 
 (provide 'ruby-mode)