Subject: Re: [bug#28274] [PATCH] gnu: Add fold-packages-in-modules.

From: Christopher Baines <[email-masked]>
Date: Thu, 31 Aug 2017 22:44:33 +0100

On Thu, 31 Aug 2017 15:20:55 +0200
[email-masked] (Ludovic Courtès) wrote:

> Instead of introducing a new procedure, what about simply:
> 
> 
> diff --git a/gnu/packages.scm b/gnu/packages.scm
> index 562906178..b4ac6661c 100644
> --- a/gnu/packages.scm
> +++ b/gnu/packages.scm
> @@ -140,17 +140,19 @@ for system '~a'")
>                directory))
>          %load-path)))
>  
> -(define (fold-packages proc init)
> -  "Call (PROC PACKAGE RESULT) for each available package, using INIT
> as -the initial value of RESULT.  It is guaranteed to never traverse
> the -same package twice."
> +(define* (fold-packages proc init
> +                        #:optional
> +                        (modules (all-modules
> (%package-module-path))))
> +  "Call (PROC PACKAGE RESULT) for each available package defined in
> one of +MODULES, using INIT as the initial value of RESULT.  It is
> guaranteed to never +traverse the same package twice."
>    (fold-module-public-variables (lambda (object result)
>                                    (if (and (package? object)
>                                             (not (hidden-package?
> object))) (proc object result)
>                                        result))
>                                  init
> -                                (all-modules
> (%package-module-path))))
> +                                modules))
>  
>  (define find-packages-by-name
>    (let ((packages (delay
> 
> 
> ?

This looks great. Are you set to push it up, or shall I?

Thanks,

Chris