Re: guix-package --search

[ludo@gnu.org (Ludovic Courtès)]

Hi,

Nikita Karetnikov <nikita@karetnikov.org> skribis:

> 1. 'psd-list' is a potential bottleneck.  It will cause problems when we
>    have more packages.  If it's possible to evaluate it lazily, I'll
>    rewrite it.  (I haven't checked yet.)

See below.

[...]

> 4. I've noticed that 'fold-packages' returns duplicates.  Should it be
>    fixed?  Should I filter the output instead?

These are not really duplicates, actually: these are variants of the
same packages, created using ‘inherit’, and keeping the original
package’s source location info (which could be fixed).

That said, it would make sense to ‘delete-duplicates’ any two packages
whose ‘package-location’ are ‘eq?’.  But that can be left as a separate
commit.

The patch looks good overall.  A few comments:

> +(define (sd-search rx)

Rather ‘find-packages-by-description’ or similar.

> +  "Search in SYNOPSIS and DESCRIPTION using RX.  Return a list of
> +matching packages."
> +  (define psd-list
> +    ;; Return a list of lists (each inner list contains PACKAGE-NAME,
> +    ;; SYNOPSIS, and DESCRIPTION of every package).
> +    (map (lambda (x)
> +           (list x (package-synopsis x) (package-description x)))
> +         (fold-packages cons '())))

Instead, you can directly build the list of matching packages, like:

  (fold-packages (lambda (package result)
                   (if (or (regexp-exec rx (package-synopsis package))
                           (regexp-exec rx (package-description package)))
                       (cons package result)
                       result))
                 '())

This way, only one traversal is done.

For i18n, we should actually use (gettext (package-description
package)), likewise for synopsis.  This way, that will search through
text in the user’s native language.

> +        (('search regexp)
> +         (let ((regexp (and regexp (make-regexp regexp))))
> +           (for-each (lambda (p)
> +                       (format #t "~a\t~a\t~a~%"
> +                               (package-name p)
> +                               (package-version p)
> +                               (location->string (package-location p))))
> +                     (sd-search regexp))
> +           #t))

Perfect.

Thanks!

Ludo’.