Re: savehist -- save minibuffer history between Emacs invocations

[Simon Josefsson]

Hrvoje Niksic <address@hidden> writes:

> define-minor-mode doesn't work under XEmacs.

Ouch.

> And from the available documentation I understand define-minor-mode
> to be pretty much equivalent to the combination of `add-minor-mode'
> and the code I've written.

define-minor-mode also create a customizable foo-mode variable, which
load and enable the mode if it is customized in ~/.emacs.

>> Then I could simply customize the savehist-mode variable, and the
>> mode would load and enable itself automatically.
>
> If you know how to correctly achieve that with `defcustom', by all
> means let me know.

How about this patch?

Index: savehist.el
===================================================================
RCS file: /home/cvs/simon/elisp/savehist.el,v
retrieving revision 1.1
diff -u -p -u -w -r1.1 savehist.el
--- savehist.el 31 Oct 2005 10:51:56 -0000      1.1
+++ savehist.el 31 Oct 2005 11:13:30 -0000
@@ -32,10 +32,10 @@
 ;; variables may be specified by customizing
 ;; `savehist-additional-variables'.
 
-;; To use savehist, turn on savehist-mode by putting the following in
-;; `~/.emacs':
+;; To use savehist, turn on savehist-mode by customizing the variable
+;; `savehist-mode', or putting the following in `~/.emacs':
 ;;
-;;     (savehist-mode 1)
+;;     (require 'savehist)
 ;;
 ;; You can also explicitly save history with `M-x savehist-save' and
 ;; load it by loading the `savehist-file' with `M-x load'.
@@ -56,9 +56,11 @@
   "Save minibuffer history."
   :group 'minibuffer)
 
-(defvar savehist-mode nil
-  "Mode for automatic saving of minibuffer history.
-Set this by calling `savehist-mode'.")
+(defcustom savehist-mode nil
+  "Mode for automatic saving of minibuffer history."
+  :type 'boolean
+  :require 'savehist
+  :group 'savehist)
 
 (defcustom savehist-save-minibuffer-history t
   "*If non-nil, save all recorded minibuffer histories.
@@ -348,6 +350,9 @@ Does nothing if savehist-mode is off."
   (add-to-list 'savehist-minibuffer-history-variables
               minibuffer-history-variable))
 
+;;; Turn on the mode.
+(savehist-mode 1)
+
 (provide 'savehist)
 
 ;; arch-tag: b3ce47f4-c5ad-4ebc-ad02-73aba705cf9f