From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=)
Subject: Re: wip-signed-archives progress report
Date: Fri, 28 Mar 2014 00:34:08 +0100
Message-ID: <87eh1ntdvz.fsf@gnu.org>
References: <878urwzhpt.fsf@gnu.org> <87d2h78vn4.fsf@karetnikov.org>
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To: Nikita Karetnikov <nikita@karetnikov.org>
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Nikita Karetnikov <nikita@karetnikov.org> skribis:

>> Nikita: comments welcome on the two commits I just pushed in
>> wip-signed-archives.
>
> Thanks for working on it.  One question: in the past, you told me to
> avoid =E2=80=98false-if-exception=E2=80=99.  If it=E2=80=99s an issue her=
e, can we replace it
> with something else?

What did I say?  :-)  (We have a saying in French: =E2=80=9Cdo what I say, =
not
what I do=E2=80=9D.  ;-))

I used it in two places:

                   (false-if-exception
                    (and=3D> signature narinfo-signature->canonical-sexp))

and:

  (define (valid-narinfo? narinfo)
    "Return #t if NARINFO's signature is not valid."
    (false-if-exception (begin (assert-valid-narinfo narinfo) #t)))

=E2=80=98false-if-exception=E2=80=99 should indeed be used with care, becau=
se it hides
every error (including unbound var errors and such!), so it could be
hiding errors that really ought to be reported.

In the above cases I considered it OK, because the set of exceptions
that can possibly be raised is limited, and because the outcome of
=E2=80=98false-if-exception=E2=80=99 is conservative (that is, at worst all=
 narinfos
will be treated as if they were unsigned or invalid.)

Does it makes sense?

Ludo=E2=80=99.