bug#6997: Loading w32-fns under X11 signals an error

[Stefan Monnier]

>> The title says it.  It probably also messes with things, additionally to
>> signalling an error.  Of course, you will say "don't do that", but
>> remember that files may be loaded for all kinds of reasons, so they
>> should be harmless.

> "Harmless" in what sense?

That Emacs works as well after loading the file than before.
You know, like language extensions: they do change the semantics of the
language but in a way that's usually accepted as "harmless": it only
gives meaning to things which earlier were errors.

> Should they do nothing at all?  Probably
> not, or else you wouldn't be loading them, right?

They can define new functions and variables, as well as load other
files, and even set a few things up but only to *add* behavior, not to
*change* behavior.

> Even in your specific use-case, did you want the w32-fns functions to
> end up in the obarray or not?

Of course, that was the whole point since I wanted to complete on
function names.

> IOW, can you come up with a general enough definition of the reason(s)
> for loading w32-fns on non-w32 systems?

The same reason why I might want to load diff-mode.el without ever
wanting to use that mode.

E.g. to complete function/variable names, or to browse customize data, ...


        Stefan