bug#26275: [PATCH] build: perl-build-system: Add `wrap' phase.

[Arun Isaac]

> +(define* (wrap #:key inputs outputs #:allow-other-keys)
> +  (define (list-of-files dir)
> +    (map (cut string-append dir "/" <>)
> +         (or (scandir dir (lambda (f)
> +                            (let ((s (stat (string-append dir "/" f))))
> +                              (eq? 'regular (stat:type s)))))
> +             '())))
> +
> +  (define bindirs
> +    (append-map (match-lambda
> +                  ((_ . dir)
> +                   (list (string-append dir "/bin")
> +                         (string-append dir "/sbin"))))
> +                outputs))
> +
> +  (let* ((out  (assoc-ref outputs "out"))
> +         (var `("PERL5LIB" prefix
> +                ,(search-path-as-string->list
> +                  (or (getenv "PERL5LIB") "")))))
> +    (for-each (lambda (dir)
> +                (let ((files (list-of-files dir)))
> +                  (for-each (cut wrap-program <> var)
> +                            files)))
> +              bindirs)))

I copied this wrap function from the python build system, and modified
it a little to suite perl. Is there any reason `list-of-files' and
`bindirs' are initialized using `define' rather than a `let' binding?
This is probably a very basic Guile question, but still...

Thanks,
Arun Isaac.