Re: Trouble using (current-filename)

[ludo@gnu.org (Ludovic Courtès)]

Hello!

Andy Wingo <wingo@pobox.com> skribis:

> On Sun 19 Feb 2012 15:10, ludo@gnu.org (Ludovic Courtès) writes:
>
>> Andy Wingo <wingo@pobox.com> skribis:
>>
>>> On Fri 17 Feb 2012 23:49, ludo@gnu.org (Ludovic Courtès) writes:
>>>
>>>> Would it work to let the user call it themself if needed, like:
>>>>
>>>>   (add-to-load-path (dirname (canonicalize-path (current-filename))))
>>>
>>> I would rather have current-filename do a
>>>
>>>   (or (false-if-exception (canonicalize-path p)) p)
>>>
>>> Current-filename sounds like it should do the right thing, if possible.
>>
>> I think it’s often undesirable.
>>
>> Suppose you want to use ‘current-filename’ in an ‘assert’ macro, for
>> instance: what you want is a hint, not an absolute path, since that path
>> is likely to be invalid at the time you see it (for instance, it could
>> point to the source tree on a build machine of your distro.)
>>
>> Furthermore, including absolute paths by default makes builds
>> non-deterministic: two users would get different binaries, just because
>> they built things under a different directory.
>>
>> Thus, I’d rather let users call ‘canonicalize-path’ when they know what
>> they’re doing, and know that they actually need it.
>>
>> WDYT?
>
> I'm fine with that, but I think you are concerned more about code in
> modules (compiled in one location, installed and run from another) than
> for local scripts.

Yes.

> See Neil's use case here:
>
>   http://thread.gmane.org/gmane.lisp.guile.devel/13440/focus=13621
>
> Can we do something that makes sense for both cases?

Well, (add-to-load-path (dirname (canonicalize-path (current-filename)))) ?

Yes it’s verbose, but it’s predictable and clearly specified.

Ludo’.