[bug#28690] provide a lib output for boost

[Ludovic Courtès]

Dave Love <address@hidden> skribis:

> Ludovic Courtès <address@hidden> writes:
>
>> The choice was made to allow package definitions to explicitly state
>> which outputs of their dependencies they’re interested in.  So it you
>> have
>>
>>   `("boost" ,boost)
>>
>> that’s only boost:out; if you have:
>>
>>   `("boost" ,boost "lib")
>>
>> that’s only boost:lib.  If you want both, you need to specify both.
>>
>> So far I don’t think this was considered a problem; on the contrary, you
>> could get fine-grain control, as in glib:out vs. glib:bin.  In this
>> particular case, I agree that it’s annoying to have to specify both.
>>
>> If this “particular case” happens to be common enough, we can always
>> revisit the above decision and chance `("boost" ,boost) to mean “all the
>> outputs of boost.”
>
> It looks to me that it will be common if you want to reduce closures.
> Also, in other distributions you know that you can build-depend on the
> -dev(el) package and get what you need without having to know about
> various sub-packages (outputs), and the runtime requirements should be
> minimal (although there are sometimes problems with unnecessary
> dependencies).  As far as I know, Guix doesn't have an easy way to find
> what provides particular files to determine the inputs.

Yeah, you may be right.  Nixpkgs took that route when they introduced
multiple outputs not long ago.

Well, something to experiment with I guess!

Thanks,
Ludo’.