Re: helpex.el 0.2 --- useful extensions for the C-h prefix

[Stefan Monnier <monnier@iro.umontreal.ca>]

> Hmm, unannounced Followup-To. Is that best current practice here in gnu.*?

I sometimes get tired of writing the same stuff over and over again, so
when redirecting discussions from gnu.emacs.sources to gnu.emacs.help,
I don't always do it "properly".  Especially because I think it's the role
of the newsreader to announce when followup is set to something else.

>> I haven't used p-c-m in a while and I use C-a SPC 
> Do you mean C-q SPC?

Oops, yes, indeed.  Sorry for the typo.

>> to insert a space, so
>> I wouldn't know.  If it works without p-c-m, then it's a bug in p-c-m,
>> otherwise it's a misfeature.
> It's most likely a bug in p-c-m. On the other hand, without p-c-m,
> when you hit TAB twice after entered the full file name (e.g.
> "(emacs)"), you first get "[Complete, but not unique]" and on the
> second try "[No completions]".  Maybe that's irritating p-c-m.

Sounds like a problem indirectly due to the fact that the completion
commands like TAB do not know how to deal with a completion-table that
"doesn't work".  Or seen from the other side, there's no way for the
completion table to tell the completion commands that "completion doesn't
work here".  So instead, the completion table lies and says things like
"this is valid text" (since potentially all is valid) but it also returns
an empty list of possible completions (even though the first response
implies that the current text is one valid completion).

Maybe we should extend `try-completion's interface to return `no-completion'
when completion is unavailable, so the completion commands can then output
some more meaningful message.


        Stefan