Re: Minibuffer default values list

[Juri Linkov <juri@jurta.org>]

>     If you don't want loading mailcap.el on M-! then what do you think about
>     loading mailcap.el only when the user types M-n in the shell command's
>     minibuffer?
>
> That is an interesting approach.

Below is a patch that implements this approach.

It adds a new variable `goto-history-element-pre-hook' run at the beginning
of `goto-history-element'.  And `shell-command' binds it to a function
that after typing e.g. `M-n M-n' and going to the second default value
(the first element is a static value set to the current file name)
adds more commands extracted from mailcap to `minibuffer-default'.
`dired-read-shell-command' below does the same.

Index: lisp/simple.el
===================================================================
RCS file: /sources/emacs/emacs/lisp/simple.el,v
retrieving revision 1.889
diff -c -r1.889 simple.el
*** lisp/simple.el	15 Nov 2007 16:42:43 -0000	1.889
--- lisp/simple.el	24 Nov 2007 17:54:00 -0000
***************
*** 1298,1307 ****
--- 1298,1311 ----
  
  (defvar minibuffer-temporary-goal-position nil)
  
+ (defvar goto-history-element-pre-hook nil
+   "*List of functions run by `goto-history-element' before changing history position.")
+ 
  (defun goto-history-element (nabs)
    "Puts element of the minibuffer history in the minibuffer.
  The argument NABS specifies the absolute history position."
    (interactive "p")
+   (run-hooks 'goto-history-element-pre-hook)
    (let ((minimum (if minibuffer-default
  		     (- (if (listp minibuffer-default)
  			    (length minibuffer-default)
***************
*** 1962,1971 ****
  In an interactive call, the variable `shell-command-default-error-buffer'
  specifies the value of ERROR-BUFFER."
  
!   (interactive (list (read-from-minibuffer "Shell command: "
! 					   nil nil nil 'shell-command-history)
! 		     current-prefix-arg
! 		     shell-command-default-error-buffer))
    ;; Look for a handler in case default-directory is a remote file name.
    (let ((handler
  	 (find-file-name-handler (directory-file-name default-directory)
--- 1966,1988 ----
  In an interactive call, the variable `shell-command-default-error-buffer'
  specifies the value of ERROR-BUFFER."
  
!   (interactive
!    (let* ((filename
! 	   (if buffer-file-name (file-relative-name buffer-file-name)))
! 	  (default filename)
! 	  (minibuffer-default-set nil)
! 	  (goto-history-element-pre-hook
! 	   (cons (lambda ()
! 		   (when (and (null minibuffer-default-set) (< nabs -1))
! 		     (setq minibuffer-default
! 			   (cons filename (dired-read-shell-command-default
! 					   (list filename))))
! 		     (setq minibuffer-default-set t)))
! 		 goto-history-element-pre-hook)))
!      (list (read-from-minibuffer "Shell command: " nil nil nil
! 				 'shell-command-history default)
! 	   current-prefix-arg
! 	   shell-command-default-error-buffer)))
    ;; Look for a handler in case default-directory is a remote file name.
    (let ((handler
  	 (find-file-name-handler (directory-file-name default-directory)

Index: lisp/dired-aux.el
===================================================================
RCS file: /sources/emacs/emacs/lisp/dired-aux.el,v
retrieving revision 1.160
diff -c -r1.160 dired-aux.el
*** lisp/dired-aux.el	22 Nov 2007 13:49:34 -0000	1.160
--- lisp/dired-aux.el	24 Nov 2007 17:54:25 -0000
***************
*** 517,528 ****
  ;;ARG is the prefix arg and may be used to indicate in the prompt which
  ;;  files are affected.
  ;;This is an extra function so that you can redefine it, e.g., to use gmhist."
!   (dired-mark-pop-up
!    nil 'shell files
!    (function read-string)
!    (format prompt (dired-mark-prompt arg files))
!    nil 'shell-command-history
!    (dired-read-shell-command-default files)))
  
  ;; The in-background argument is only needed in Emacs 18 where
  ;; shell-command doesn't understand an appended ampersand `&'.
--- 517,534 ----
  ;;ARG is the prefix arg and may be used to indicate in the prompt which
  ;;  files are affected.
  ;;This is an extra function so that you can redefine it, e.g., to use gmhist."
!   (let ((minibuffer-default-set nil)
! 	(goto-history-element-pre-hook
! 	 (cons (lambda ()
! 		 (when (and (null minibuffer-default-set) (< nabs 0))
! 		   (setq minibuffer-default (dired-read-shell-command-default files)
! 			 minibuffer-default-set t)))
! 	       goto-history-element-pre-hook)))
!     (dired-mark-pop-up
!      nil 'shell files
!      (function read-string)
!      (format prompt (dired-mark-prompt arg files))
!      nil 'shell-command-history)))
  
  ;; The in-background argument is only needed in Emacs 18 where
  ;; shell-command doesn't understand an appended ampersand `&'.

-- 
Juri Linkov
http://www.jurta.org/emacs/