bug#67696: 30.0.50; Help deal with multiple versions in load-path

[Stefan Kangas]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>> Right.  On the other hand, perhaps hitting the file system is to some
>> extent expected once you start asking for libraries to be loaded.  You
>> only get the best case `(memq F features)' if that evaluates to `t'.
>
> For top-level uses of `require`, the performance impact is negligible.
> But for `require`s used within functions (basically performing manual
> autoloads), I'm worried that it could be problematic.
>
>> Personally, I don't have a good view of how common these problems are.
>> Perhaps they are relatively uncommon, and it's too much to ask all users
>> of `require' to pay a cost for added correctness in unusual cases.
>
> I don't either.  That's why I preferred to define a new function, which
> lets us gain some experience with it.  We may later opt to merge (some
> of) its functionality into `require`, of course.

Makes sense to me, thanks.