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Subject: [bug#38408] [PATCH v4 1/6] gnu: added new function,
 find-packages-by-name*/direct
Resent-Message-ID: <handler.38408.B38408.157679285720231@debbugs.gnu.org>
From: Ludovic =?UTF-8?Q?Court=C3=A8s?= <ludo@gnu.org>
References: <cover.1576005195.git.mjbecze@riseup.net>
 <d83466c676763462ce625fe04df176c7681fc836.1576005195.git.mjbecze@riseup.net>
Date: Thu, 19 Dec 2019 23:00:36 +0100
In-Reply-To: <d83466c676763462ce625fe04df176c7681fc836.1576005195.git.mjbecze@riseup.net>
 (Martin Becze's message of "Tue, 10 Dec 2019 14:23:38 -0500")
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To: Martin Becze <mjbecze@riseup.net>
Cc: 38408@debbugs.gnu.org

Hello!

I=E2=80=99m not a Crate expert so I=E2=80=99m only commenting on non-Crate-=
specific
bits.

Martin Becze <mjbecze@riseup.net> skribis:

> * gnu/packages.scm (find-packages-by-naem*/direct)

[...]

> +(define* (fold-packages* proc init
> +                        #:optional
> +                        (modules (all-modules (%package-module-path)
> +                                              #:warn
> +                                              warn-about-load-error))
> +                        #:key (select? (negate hidden-package?)))
> +  "Call (PROC PACKAGE RESULT) for each available package defined in one =
of
> +MODULES that matches SELECT?, using INIT as the initial value of RESULT.=
  It
> +is guaranteed to never traverse the same package twice."
> +  (fold-module-public-variables* (lambda (module symbol var result)
> +                                   (let ((object (variable-ref var)))
> +                                     (if (and (package? object) (select?=
 object))
> +                                         (proc module symbol object  res=
ult)

I=E2=80=99m wary of exposing variable names, especially in such a central A=
PI.

> +(define find-packages-by-name*/direct              ;bypass the cache

Providing an explicit cache bypassing method also sounds worrying to me:
the cache is supposed to be transparent and semantics-preserving.

More generally, I think adding new features to an importer shouldn=E2=80=99t
require modifications in this area, as a matter of separating concerns.

WDYT?

Thanks,
Ludo=E2=80=99.