bug#16577: Add regexp-based version of completion-ignored-extensions

[Lars Ingebrigtsen]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

> [ Not sure I'd bother with the non-regexp variable (other than having to
>   use \\. to match a dot, a regexp should work just as well).  ]

Well, the semantics for completion-ignored-files would be that they
match on file names (i.e., the part after the last "/" if there's any
slashes in there), which sounds like a pretty attractive thing, while
completion-ignored-files would have no anchoring.

completion-ignored-files could be regexps with anchoring, too, but then
we'd have two regexp variables, which seems excessive again.  :-/

> This is the best way long term, yes.  We could mark
> `completion-ignored-extensions` as obsolete and in a few years we're
> back with a clean semantics and a simple variable.

I like completion-ignored-extensions -- it's clear what it does and easy
to alter both programmatically and for users.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no