Re: [PATCH 7/8] Makefile: stop having command-list.h depend on a wildcard

From: Junio C Hamano <gitster@pobox.com>
Date: Oct 21, 2021, 18:24 UTC
Message-ID: <xmqq4k9ame1q.fsf@gitster.g>
In-Reply-To: <YXF9DQuj0541ULku@coredump.intra.peff.net>

Jeff King <peff@peff.net> writes:

Show 18 quoted lines

> On Wed, Oct 20, 2021 at 08:39:58PM +0200, Ævar Arnfjörð Bjarmason wrote:
>
>>  get_synopsis () {
>> +	head -n 10 "Documentation/$1.txt" |
>>  	sed -n '
>>  		/^NAME/,/'"$1"'/H
>>  		${
>>  			x
>>  			s/.*'"$1"' - \(.*\)/N_("\1")/
>>  			p
>> -		}' "Documentation/$1.txt"
>> +		}'
>>  }
>
> By the way, I'm not sure about the utility of this change. It reduces
> the number of lines that sed looks at, but at the cost of an extra
> process. That's probably a net loss. And if we did want to limit the
> data sed covers, doing "pq" after we matched would be simpler.

Doesn't the above

 - slurp the lines into hold space while we are in the synopsis
   part;
 - otherwise keep reading and discarding;
 - and do the processing at end

So presumably, instead of waiting till the end, can't we immediately process the thing and exit?

I guess your "'pq' after we matched" is saying the same thing. I agree that extra process with an ad-hoc limitation of 10 does leave a bad taste in my mouth.