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From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=)
Subject: Re: [PATCH] guix package: Show which generation is the current one.
Date: Tue, 24 Sep 2013 16:16:51 +0200
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In-Reply-To: <87wqm6tjd5.fsf@karetnikov.org> (Nikita Karetnikov's message of
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To: Nikita Karetnikov <nikita@karetnikov.org>
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Nikita Karetnikov <nikita@karetnikov.org> skribis:

>> Could we instead of a global (current-generation-number profile)
>> procedure?  We=E2=80=99d store the number in a local variable here, to a=
void
>> repeated =E2=80=98readlink=E2=80=99 calls.
>
> I don=E2=80=99t see how the former implies the latter.  Could you expand =
on
> this?

I=E2=80=99m suggesting to have a procedure like this:

  (define (current-generation-number profile)
    ;; Return the current generation number of PROFILE.
    ...)

And then you could do:

  (let ((generation (current-generation-number profile)))
    ...)

Does that make sense?

Ludo=E2=80=99.