Re: image.el doesn't associate image-mode with .JPG files

[Kim F. Storm]

"Juanma Barranquero" <address@hidden> writes:

> image.el already defines `image-type-header-regexps' and
> `image-type-from-buffer', so it seems wasteful to recreate that. It
> would be better IMHO to simply use `image-type-from-buffer' from
> `set-auto-mode'. Other than changes to docstrings and info files, the
> path is as simple as this, and works quite well.

I think your idea is really good -- and simple!

Another way is the following one which does exactly the same as your
patch, but in a more generic way:


*** files.el    11 Dec 2006 09:41:20 +0100      1.868
--- files.el    17 Dec 2006 01:24:31 +0100      
***************
*** 2115,2121 ****
  associated with that interpreter in `interpreter-mode-alist'.")
  
  (defvar magic-mode-alist
!   `(;; The < comes before the groups (but the first) to reduce backtracking.
      ;; TODO: UTF-16 <?xml may be preceded by a BOM 0xff 0xfe or 0xfe 0xff.
      ;; We use [ \t\n] instead of `\\s ' to make regex overflow less likely.
      (,(let* ((incomment-re "\\(?:[^-]\\|-[^-]\\)")
--- 2115,2122 ----
  associated with that interpreter in `interpreter-mode-alist'.")
  
  (defvar magic-mode-alist
!   `((image-type-from-buffer . image-mode)
!     ;; The < comes before the groups (but the first) to reduce backtracking.
      ;; TODO: UTF-16 <?xml may be preceded by a BOM 0xff 0xfe or 0xfe 0xff.
      ;; We use [ \t\n] instead of `\\s ' to make regex overflow less likely.
      (,(let* ((incomment-re "\\(?:[^-]\\|-[^-]\\)")
***************
*** 2134,2143 ****
      ("%![^V]" . ps-mode)
      ("# xmcd " . conf-unix-mode))
    "Alist of buffer beginnings vs. corresponding major mode functions.
! Each element looks like (REGEXP . FUNCTION).  After visiting a file,
! if REGEXP matches the text at the beginning of the buffer,
! `normal-mode' will call FUNCTION rather than allowing `auto-mode-alist'
! to decide the buffer's major mode.
  
  If FUNCTION is nil, then it is not called.  (That is a way of saying
  \"allow `auto-mode-alist' to decide for these files.\")")
--- 2135,2145 ----
      ("%![^V]" . ps-mode)
      ("# xmcd " . conf-unix-mode))
    "Alist of buffer beginnings vs. corresponding major mode functions.
! Each element looks like (REGEXP . FUNCTION) or (MATCH-FUNCTION . FUNCTION).
! After visiting a file, if REGEXP matches the text at the beginning of the
! buffer, or calling MATCH-FUNCTION returns non-nil, `normal-mode' will
! call FUNCTION rather than allowing `auto-mode-alist' to decide the buffer's
! major mode.
  
  If FUNCTION is nil, then it is not called.  (That is a way of saying
  \"allow `auto-mode-alist' to decide for these files.\")")
***************
*** 2224,2230 ****
                                                (+ (point-min) 
magic-mode-regexp-match-limit)))
                         (assoc-default nil magic-mode-alist
                                        (lambda (re dummy)
!                                         (looking-at re))))))
          (set-auto-mode-0 done keep-mode-if-same)
        ;; Compare the filename against the entries in auto-mode-alist.
        (if buffer-file-name
--- 2226,2234 ----
                                                (+ (point-min) 
magic-mode-regexp-match-limit)))
                         (assoc-default nil magic-mode-alist
                                        (lambda (re dummy)
!                                         (if (functionp re)
!                                             (funcall re)
!                                           (looking-at re)))))))
          (set-auto-mode-0 done keep-mode-if-same)
        ;; Compare the filename against the entries in auto-mode-alist.
        (if buffer-file-name

-- 
Kim F. Storm <address@hidden> http://www.cua.dk