Re: Request: Emacs configuration file locations needs upgrade

[Jari Aalto+mail.emacs]

* Tue 2001-01-02 eliz@is.elta.co.il (Eli Zaretskii) gnu.emacs.bug
* 
<http://search.dejanews.com/msgid.xp?MID=%3CPine.SUN.3.91.1010102113903.18307L-100000@is%3E&format=threaded>
| On 2 Jan 2001, Jari Aalto+mail.emacs wrote:
| 
| >     Emacs should offer a function interface to the configuration
| >     files, which all package developers use. The functions
| >     would generate the default name and the location for the filename.
| >     User configurable variables would control the directory, PREFIX
| >     and POSTFIX for the files.
| 
| While this change sounds like a useful feature, I wonder what will
| happen with the default file names?

See below.
 
| If the default file names shall change in any way, we will create a
| backwards-compatibility problem, which will undoubtfully make users
| unhappy.  Note that some of these file names, like ~/.emacs-places,
| are in use for a very long time.

This can be solved. The default filenames could stay as they are. All
what is needed is intermediate-backward-compatibility-function that
will select the correct interface according to user's preference: 


Jari
    
I some package:

    (defcustom package-file (config-file-backward-compatibility
                             "~/.original-name"
                             "package" "name"
                            )
        ...

The configuration file interface:

    (defvar config-file-use-bacward-compatibility t
      "*Flag to use old Emacs configutation file interface.")

    (defun config-file-backward-compatibility (abs-location pkg file)
       "Select backward or new implementation."
       (if config-file-use-bacward-compatibility
           abs-location
         (config-file-name pkg name)))