[bug#50620] [PATCH 1/2] guix: packages: Document 'computed-origin-method'.

[zimoun <zimon.toutoune@gmail.com>]

Hi Liliana and Mark,

Thanks for the comments.

On Fri, 17 Sept 2021 at 01:40, Mark H Weaver <mhw@netris.org> wrote:
> Liliana Marie Prikler <liliana.prikler@gmail.com> wrote:

> > I think that rather than putting this into (guix packages) itself, we
> > might want to put it into its own file like (guix computed-origins) and
> > choose a method name that is actually a verb, similar to git-fetch or
> > svn-fetch.  Perhaps simply call it compute-origin?
>
> These suggestions sound fine to me, although I don't have a strong
> opinion either way.  I'm happy to leave these details to others to
> decide.

I do not have a strong opinion either.  If no one comes with a better
name, I will pick the suggested one. :-)

        There are only two hard things in Computer Science: cache
        invalidation and naming things.
                                                      -- Internet


> > If done this way, there'd be the benefit that modules with packages
> > using this thing would have to explicitly request the presence of the
> > symbol through their use-modules clauses.
>
> Actually, for better or worse, Guile's '@@' form does not require the
> named module to be imported using 'use-modules', so I don't think this
> benefit strictly exists as stated above.  However, I agree that it's
> good practice to list all imported modules in the '#:use-module' clauses
> at the top of the file wherever possible [*], and that there may be some
> benefit in declaring the use of 'computed-origins' at the top of each
> file.

I am not deeply familiar with Guile module.

I chose to put this in (guix packages) instead of its own module
because the module would contain only one function and nothing
exported.  The aim for now, as discussed, is to not make this 'method'
part of the public API.

Then if the function is not exported by the module, the '#:use-module'
does not have an effect, right?

In this case, does it make sense to put this in its own module?

Initially, I put the '@@' right after the '#:use-module's but then I
changed my mind; I do not remember why.  Anyway, yeah it is better at
the top.


Cheers,
simon