From: "Ludovic Courtès" <ludo@gnu.org>
To: Ricardo Wurmus <rekado@elephly.net>
Cc: 36772@debbugs.gnu.org, Robert Vollmert <rob@vllmrt.net>
Subject: bug#36772: feature request: checked variant of "substitute*"
Date: Thu, 25 Jul 2019 19:40:48 +0200 [thread overview]
Message-ID: <875znqrp0f.fsf@gnu.org> (raw)
In-Reply-To: <87zhl4c1rc.fsf@elephly.net> (Ricardo Wurmus's message of "Tue, 23 Jul 2019 15:35:19 +0200")
Hi,
Ricardo Wurmus <rekado@elephly.net> skribis:
>> I think it would be great to have the following variant of substitute*:
>>
>> (substitute*-once filename (pattern vars) body)
>>
>> which acts like the usual substitute-*, except it also asserts that the
>> substitution applies to exactly one line in the file, causing a build
>> failure otherwise.
>
> I agree that the effect of substitute* should be checked. I think
> substitute* should fail when one of its clauses failed to match
> anything.
>
> Each clause could also accept an optional argument to make them only
> match one location. We wouldn’t have to duplicate the macro for that
> and it’s a simple extension to failing on zero matches.
>
> What do you think?
That’d be a useful extension.
Ludo’.
prev parent reply other threads:[~2019-07-25 17:41 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-23 12:49 bug#36772: feature request: checked variant of "substitute*" Robert Vollmert
2019-07-23 13:35 ` Ricardo Wurmus
2019-07-23 13:41 ` Robert Vollmert
2019-07-25 17:40 ` Ludovic Courtès [this message]
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