Suggestion for C-h f, describe-function

[David Kastrup <dak@gnu.org>]

Hi, when using C-h f describe-function RET on a function defined in C,
the hyperlink with the source file name takes me to the Emacs source
code tree, which is very convenient.

Doing the same on a Lisp function will instead take me to the actually
loaded file in the installed tree which is quite less convenient since
it means that I constantly have some duplicated buffers with the same
content, and since it means if I do any actual changes to fix
something and try checking them in or comparing versions, this will
fail since I always manage to get the version _not_ under version
control.

Would it be possible to add an option where the source tree was
consulted also for the Lisp files?  There would be the additional
problem that while all sources to C functions are, of course, in the
Emacs source tree, this does not hold for the Lisp tree, so one should
probably have a way to specify different source trees for different
things in the Emacs tree, like mapping the prefix
/usr/local/share/emacs-22.0.50/lisp to "/usr/local/src/emacs/lisp", and
/usr/local/share/emacs/site-lisp/auctex to try both
"/usr/local/src/auctex/preview" and "/usr/local/src/auctex"

Maybe such a list would be specified as something like

(("^/usr/local/share/emacs-22.0.50/lisp/"
     "/usr/local/src/emacs/lisp/\\&")
 ("^/usr/local/share/emacs/site-lisp/auctex/"
     "/usr/local/src/auctex/preview/\\&"
     "/usr/local/src/auctex/\\&"))

which will do the obvious regexp replacements for finding the source
files.

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum