diff options
Diffstat (limited to 'lisp')
| -rw-r--r-- | lisp/files.el | 76 |
1 files changed, 42 insertions, 34 deletions
diff --git a/lisp/files.el b/lisp/files.el index 888f9dc81e9..901e0a65f6b 100644 --- a/lisp/files.el +++ b/lisp/files.el @@ -1845,20 +1845,27 @@ be interpreted by the interpreter matched by the second group of the regular expression. The mode is then determined as the mode associated with that interpreter in `interpreter-mode-alist'.") -(defvar xml-based-modes '(html-mode) - "Modes that override an XML declaration. -When `set-auto-mode' sees an <?xml or <!DOCTYPE declaration, that -buffer will be in some XML mode. If `auto-mode-alist' associates -the file with one of the modes in this list, that mode will be -used. Else `xml-mode' or `sgml-mode' is used.") +(defvar magic-mode-alist + '(;; The < comes before the groups (but the first) to reduce backtracking. + ;; Is there a nicer way of getting . including \n? + ;; TODO: UTF-16 <?xml may be preceded by a BOM 0xff 0xfe or 0xfe 0xff. + ("\\(?:<\\?xml\\s +[^>]*>\\)?\\s *<\\(?:!--\\(?:.\\|\n\\)*?-->\\s *<\\)*\\(?:!DOCTYPE\\s +[^>]*>\\s *<\\)?\\s *\\(?:!--\\(?:.\\|\n\\)*?-->\\s *<\\)*[Hh][Tt][Mm][Ll]" . html-mode) + ;; These two must come after html, because they are more general: + ("<\\?xml " . xml-mode) + ("\\s *<\\(?:!--\\(?:.\\|\n\\)*?-->\\s *<\\)*!DOCTYPE " . sgml-mode) + ("%![^V]" . ps-mode)) + "Alist of buffer beginnings vs corresponding major mode functions. +Each element looks like (REGEXP . FUNCTION). FUNCTION will be +called, unless it is nil.") (defun set-auto-mode (&optional keep-mode-if-same) "Select major mode appropriate for current buffer. + This checks for a -*- mode tag in the buffer's text, checks the interpreter that runs this file against `interpreter-mode-alist', -looks for an <?xml or <!DOCTYPE declaration (see -`xml-based-modes'), or compares the filename against the entries -in `auto-mode-alist'. +compares the buffer beginning against `magic-mode-alist', +or compares the filename against the entries in +`auto-mode-alist'. It does not check for the `mode:' local variable in the Local Variables section of the file; for that, use `hack-local-variables'. @@ -1917,32 +1924,33 @@ only set the major mode, if that would change it." ;; Map interpreter name to a mode, signalling we're done at the ;; same time. done (assoc (file-name-nondirectory mode) - interpreter-mode-alist)) - ;; If we found an interpreter mode to use, invoke it now. - (if done (set-auto-mode-0 (cdr done) keep-mode-if-same))) - (if (and (not done) buffer-file-name) - (let ((name buffer-file-name)) - ;; Remove backup-suffixes from file name. - (setq name (file-name-sans-versions name)) - (while name - ;; Find first matching alist entry. - (let ((case-fold-search - (memq system-type '(vax-vms windows-nt cygwin)))) - (if (and (setq mode (assoc-default name auto-mode-alist + interpreter-mode-alist))) + ;; If we found an interpreter mode to use, invoke it now. + (if done + (set-auto-mode-0 (cdr done) keep-mode-if-same) + (if (setq done (save-excursion + (goto-char (point-min)) + (assoc-default nil magic-mode-alist + (lambda (re dummy) + (looking-at re))))) + (set-auto-mode-0 done keep-mode-if-same) + (if buffer-file-name + (let ((name buffer-file-name)) + ;; Remove backup-suffixes from file name. + (setq name (file-name-sans-versions name)) + (while name + ;; Find first matching alist entry. + (let ((case-fold-search + (memq system-type '(vax-vms windows-nt cygwin)))) + (if (and (setq mode (assoc-default name auto-mode-alist 'string-match)) - (consp mode) - (cadr mode)) - (setq mode (car mode) - name (substring name 0 (match-beginning 0))) - (setq name))) - (when mode - (if xml (or (memq mode xml-based-modes) - (setq mode 'xml-mode))) - (set-auto-mode-0 mode keep-mode-if-same) - (setq done t))))) - (and xml - (not done) - (set-auto-mode-0 'xml-mode keep-mode-if-same)))) + (consp mode) + (cadr mode)) + (setq mode (car mode) + name (substring name 0 (match-beginning 0))) + (setq name))) + (when mode + (set-auto-mode-0 mode keep-mode-if-same))))))))) ;; When `keep-mode-if-same' is set, we are working on behalf of |