Re: cc-vars.el

[Martin Stjernholm <mast@lysator.liu.se>]

Miles Bader <miles@gnu.org> wrote:

> It's not that I hate explicit pragmas with a passion or anything; if someone
> can get something past rms, I guess that's fine with me; but no one's
> presented much evidence in this thread that they're actually needed, and it'd
> be nice to see what things they _are_ needed for -- and anyway, we need that
> to design the pragmas anyway...  Did I miss something?

I've looked through the things I've used the cc-bytecomp kludges for
in CC Mode, and sure enough, simple patterns for if and cond would
take care of most things.

However, some rather large parts exist only to add language knowledge
to various external packages that are optional and might not be
available at all. Putting conditionals outside the whole set of
defconsts, defuns etc would then be necessary to silence the compiler.
But doing so would give load order dependencies (i.e. it wouldn't work
if the optional packages gets loaded later). And coping with that
would require an eval-after-load around the whole thing..

Another more design-wise argument for providing them is that
programming tools should be orthogonal to make sure all possible cases
are covered. The stance that pragmas can get implemented when someone
needs them aren't good since it'd be a considerable obstacle if a
non-emacs core developer actually encounters such a situation. It's
probably more likely that an ugly kludge is devised instead.