Hi Maxime & Sarah,

Ludovic Courtès <ludo@gnu.org> skribis:

> Hmm, thinking out loud, what about this: use the same trick as you did,
> but replace ‘define-public’ instead of ‘let’ & co., so as to be less
> intrusive.
>
>   (define-syntax-parameter current-definition-location
>     (identifier-syntax #f))
>
>   (define-syntax define-public*
>     (syntax-rules ()
>       ((_ prototype body)
>        (define-public prototype
>          (syntax-parameterize ((current-definition-location
>                                 (identifier-syntax (current-source-location))))
>            body)))))
>
> Since there’s code that assumes ‘package-location’ returns the location
> of the (package …) sexp, we could add a ‘definition-location’ field in
> <package>, defaulting to ‘current-definition-location’, or tweak
> ‘location’ to include both.

Below is an attempt at doing this.  As discussed on IRC, the first patch
switches the ‘location’ field to a more compact format that may reduce
load time by a tiny bit, though it’s hard to measure.  The second patch
introduces an extra field for the definition location; that means that
<package> records now occupy an extra word, which is not great, but
unfortunately OTOH location is slightly smaller.

Example:

--8<---------------cut here---------------start------------->8---
scheme@(guile-user)> ,use(gnu packages base)
scheme@(guile-user)> ,use(gnu packages accessibility)
scheme@(guile-user)> ,use(guix)
scheme@(guile-user)> (package-location footswitch)
$1 = #<<location> file: "gnu/packages/accessibility.scm" line: 257 column: 4>
scheme@(guile-user)> (package-definition-location footswitch)
$2 = #<<location> file: "gnu/packages/accessibility.scm" line: 254 column: 0>
scheme@(guile-user)> (package-location hello)
$3 = #<<location> file: "gnu/packages/base.scm" line: 79 column: 2>
scheme@(guile-user)> (package-definition-location hello)
$4 = #<<location> file: "gnu/packages/base.scm" line: 78 column: 0>
--8<---------------cut here---------------end--------------->8---

Thoughts?

Thanks,
Ludo’.