Re: process-file and Tramp's file cache

[Stefan Monnier <monnier@IRO.UMontreal.CA>]

>> How 'bout changing Tramp's process-file to compare the command (and
>> args) against a list of "known pure commands"?  This would keep it all
>> inside Tramp, which I think I like better (tho I also agree that this
>> information is not fundamentally specific to Tramp, although currently
>> Tramp is the only package able to make use of it).

> That is also Julian's proposal. I dislike it, because there might be
> many packages Tramp has never heard about. And even for the packages
> contained in core Emacs, it will be an endless story: think about all the
> vc-BACKEND calls of list whatever.

OTOH, this list could be kept in a variable, so external packages could
easily add to it.

> The charme is also, that packages can precisely say, which file has been
> changed.

Clearly, each option has its advantages.  I'd mostly like to avoid
overengineering it, so for now I think a boolean is plenty (after all,
we currently live fairly happily with a worst-case behavior).

> Parsing `args' of `process-file' might also not a good idea,
> I believe.

It could prove problematic, indeed (I'm thinking mostly of having to
search for "status" in the argument of "cvs", having to skip the options
that might come before).

Let's go with your suggestion, but limited to a boolean for now (so the
name shouldn't end with "-list").


        Stefan