[bug#28690] provide a lib output for boost

[Dave Love]

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.

I don't think these things are fundamental, obviously, and I may just be
too set in my ways from other systems.  It's all meant as constructive
criticism, of course.