On 2019-06-05 15:54, ph10 wrote:
On Wed, 5 Jun 2019, ND via Pcre-dev wrote:
May be there is a some space for optimization there.
>> PCRE analyze subpattern in lookaround and say:
> First code unit = 'a'
> Last code unit = 'c'
>> So it already knows that "Subject length lower bound" is greater than
0.
> Isn't it?
Yes, that's true; it could easily set the lower bound to 2 from that
information. I will taks a look at that. Thanks for the idea, though it
can only be of small benefit as it will cut out only 2 match attempts.
In svn revision 1132 I see:
https://vcs.pcre.org/pcre2/code/trunk/testdata/testoutput2?r1=1132&r2=1131&pathrev=1132
/(*napla:^x|^y)/I
Capture group count = 0
May match empty string
Compile options: <none>
Overall options: anchored
Starting code units: x y
Subject length lower bound = 0
We have starting code unit. Isn't Subject length lower bound must be 1?
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