Simplifying & improving lisp-imenu-generic-expression

[Sean Whitton <spwhitton@spwhitton.name>]

Hello,

When writing CL you end up adding a bunch of your own defining forms.
E.g. my Consfigurator project has files full of defprop, defproplist and
defpropspec instead of defun.

The convention on naming these is such that something like

    (concat
     "\\(?:cl-\\)def\\(?:ine-\\)\\sw+\\s_*\\s-+ '?\\("
     (rx lisp-mode-symbol)
     "\\)")

ought to catch all of them.

The only part of lisp-imenu-generic-expression that this doesn't account
for is ignoring (defvar FOO) declarations, but that could probably be
added too.

Am I missing something obvious why this couldn't replace
lisp-imenu-generic-expression?  It's simpler, and has the significant
advantage that user's own defining forms will be automatically included.

-- 
Sean Whitton