The Emacs Widget and Custom Libraries, version 0.8

[Per Abrahamsen <abraham@dina.kvl.dk>]

I have now released the first version of the rewritten custom
library.   It is totally incompatible with the old library, so
packages that depends on the old library will (i.e. Gnus) will break
horribly.

See <URL:http://www.dina.kvl.dk/~abraham/custom/> for information
about the this release.

The advantages of the new version are:

- The API[1] is *a lot* simpler.
- The API is documented, kind of.
- The API is much more powerful and flexible.
- The API is now supported.
- The code is much simpler and easier to understand.
- All the code for editing is now in a separately useful widget library. 

The disadvantages are:

- Incompatible.
- Probably buggy.
- The user interface is much worse.

I plan to focus on helping Lars in making Red Gnus switch to the new
version, and fixing bugs.  Improving the user interface and adding new
functionality will be of low priority, but any suggestions will of
course be appreciated.  Including a patch will raise the priority
considerably. :-)

What I really *need* is someone with a deep understanding of faces in
both Emacsen to see if my current design is reasonable.  In
particular, I need an XEmacs specifier expert to see if the design is
compatible with XEmacs specifiers.  I don't plan to add specifier
support myself, but the design should allow someone else to contribute
it.

As an example, the way to declare `debug-on-error'[2] to get full
customization support would be:

	(defcustom debug-on-error nil
	  :group 'general-options
	  :type 'toggle
	  "*Non-nil means enter debugger if an error is signaled.
	Does not apply to errors handled by `condition-case'.
	If the value is a list, an error only means to enter the debugger
	if one of its condition symbols appears in the list.
	See also variable `debug-on-quit'.") 

Ain't that easy?

-- 
[1] Application Programmer Interface
[2] Gee, why was that the first variable I though of?