Re: Recursive substitute-keyword-arguments / setting default on build system

[nils@landt.email]

> Hilton Chain <hako@ultrarare.space> hat am 27.09.2023 16:13 CEST geschrieben:
> 
>  
> Hi Nils,
> 
> On Tue, 26 Sep 2023 19:08:06 +0800,
> nils@landt.email wrote:
> >
> > Hello,
> >
> > I use a slightly customized emacs package, and want to use it as the package that is used in emacs-build-system for the emacs plugins I'm using.
> > The default emacs gets garbage collected and takes quite a while to reinstall, I would like to avoid that. Also, it seems cleaner to build the plugins with the exact version that they will be used with.
> >
> > Here's what I have:
> >
> > (define emacs-package
> >   ((const
> >      ((options->transformation
> >         '((with-configure-flag . "emacs=--program-transform-name='s/^ctags$/ctags.emacs/'")))
> >       emacs))))
> >
> > (define (set-build-system-emacs plugin-package)
> >   (package
> >     (inherit plugin-package)
> >     (arguments
> >       (substitute-keyword-arguments (package-arguments plugin-package)
> >                                     ((#:emacs emacs) `,emacs-package)))))
> >
> > (map set-build-system-emacs package-list)
> >
> > From what I can tell this does work for the packages in package-list, but not for any inputs to those packages. That makes total sense to me, but I don't know how to solve it.
> > Any pointers? Or is it possible to set the default package for a build system, removing the need for this mapping altogether?
> 
> `package-input-rewriting' (documented in [1]) can be used for the
> purpose:
> 
> --8<---------------cut here---------------start------------->8---
> (map (package-input-rewriting
>       `((,emacs-minimal . ,emacs-package)
>         (,emacs . ,emacs-package)))
>      package-list)
> --8<---------------cut here---------------end--------------->8---
> 
> Thanks
> ---
> [1]: https://guix.gnu.org/en/manual/devel/en/html_node/Defining-Package-Variants.html

Thank you for the reply. I was already using package-input-rewriting (well, the /spec version of it) but supplemented it with the keyword argument substitution because I thought it only worked on the inputs / native-inputs / propagated-inputs fields.
But you are right, just the input-rewriting works!