Re: Emacs contributions, C and Lisp

["Perry E. Metzger" <perry@piermont.com>]

On Fri, 09 Jan 2015 12:39:15 -0500 Richard Stallman <rms@gnu.org>
wrote:
>   > Ok, I'll try again: let's suppose an extension that highlights
>   > chunks of code that might have side effects, or that could use
>   > multi-threading features, or that could result on calls to
>   > certain functions,
> 
> Those certainly don't need the statement structure.

It is difficult to figure out things such as whether global variables
have been assigned in a block without access to the AST. I'm sure a
very specific API could be crafted to permit it, of course, but then
someone else will want to check whether or not a variable is written
within a block protected by a lock variable. That too can be done
perhaps with a very specific API, but then someone else may want to
highlight all overloaded forms of the [] operator and not the
non-overloaded ones. One can keep going on.

By the way, when hacking on C++, I would often *very much* like to
have overloaded vs. non-overloaded operators highlighted differently.
It would make "unexpected" operator behavior a lot easier to be
aware of in advance -- one complaint in using the language is that
one is often unaware that an operator has been overloaded, so one
does not think to check what its behavioral differences from the
default may be. So, this isn't a hypothetical. Again, this is
something I'm sure a very specialized API could permit, but how many
such very specialized APIs does one want to add?

Perry
-- 
Perry E. Metzger		perry@piermont.com