Re: defining package variants automatically

[Ludovic Courtès]

Ricardo Wurmus <address@hidden> skribis:

> (define-module (gnu packages emacs-custom)
>   #:use-module (guix packages)
>   #:use-module (guix utils)
>   #:use-module (gnu packages)
>   #:use-module (gnu packages emacs)
>   #:use-module (gnu packages emacs-xyz)
>   #:use-module (guix build-system emacs))
>
> (define my-custom-emacs emacs-no-x) ; just a test
>
> (define package-with-my-emacs
>   (package-mapping
>    (lambda (pkg)
>      (package
>        (inherit pkg)
>        (name (string-append (package-name pkg) "-rekado"))
>        (arguments
>         (substitute-keyword-arguments (package-arguments pkg)
>           ((#:emacs _ '())
>            my-custom-emacs)))))
>    (lambda (pkg)
>      (eq? emacs-build-system (package-build-system pkg)))))
>
> (fold-packages (lambda (pkg result)
>                  (let ((variable-name
>                         (string->symbol (string-append (package-name pkg) 
> "-rekado"))))
>                    (module-define!
>                     (resolve-module '(gnu packages emacs-custom))

I suspect you’d need ‘resolve-interface’ here, or a call to
‘module-export!’.

But…  it’s evil!  :-)

Ludo’.