From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=)
Subject: Re: Display diffs between generations.
Date: Mon, 29 Aug 2016 18:25:29 +0200
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In-Reply-To: <87eg59izmw.fsf@gnu.org> (Roel Janssen's message of "Sun, 28 Aug
	2016 01:02:47 +0200")
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To: Roel Janssen <roel@gnu.org>
Cc: guix-devel@gnu.org

Hi Roel,

I=E2=80=99ve just tried the patch and I think it=E2=80=99s awesome!  I=E2=
=80=99ve also always
been dissatisfied with what =E2=80=98--list-generations=E2=80=99 provides=
=E2=80=94it=E2=80=99s
inconvenient as soon as you have more than a handful packages.

Perhaps we could add an optional argument to --list-generations where:

  --list-generations

would be equivalent to:

  --list-generations=3Ddiff

and:

  --list-generations=3Dfull

would restore the previous behavior.  It doesn=E2=80=99t cost much to do th=
at.

WDYT?

I have only minor stylistic comments:

Roel Janssen <roel@gnu.org> skribis:

> +(define (display-profile-content-diff profile number)

Or just =E2=80=98display-profile-diff=E2=80=99?

> +  "Display the changed packages in PROFILE with generation specified by =
NUMBER."

=E2=80=9C=E2=80=A6 compared to generation NUMBER=E2=80=9D?

> +  (define (equal-entry? first second)
> +    (string=3D (manifest-entry-item first)
> +             (manifest-entry-item second)))
> +
> +  (define* (display-entries entries #:optional (prefix " "))
> +    (for-each
> +     (match-lambda
> +       (($ <manifest-entry> name version output location _)
> +        (format #t "  ~a ~a\t~a\t~a\t~a~%"
> +                prefix name version output location)))
> +     entries))

In general, I find it clearer to define the singular form and inline the
=E2=80=98for-each=E2=80=99:

  (define display-entry
    (match-lambda =E2=80=A6))

  =E2=80=A6

  (for-each display-entry entries)

Otherwise LGTM!

Thank you for addressing this!

Ludo=E2=80=99.