Re: [pcre-dev] Calculate minimum subject length

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Author: ph10
To: pcre-dev
Subject: Re: [pcre-dev] Calculate minimum subject length
On Mon, 26 Aug 2019, I wrote:

> On Sun, 18 Aug 2019, ND via Pcre-dev wrote:
> > May be when meet (*ACCEPT) find_minlength must simply drop further
> > calculations for current branch. So the current value of "branchlength" will
> > be immediately considered as a minimum length of whole branch.
> That was not easily possible in the past, but recently there was some
> work done which might make it simple to do now. I will look further at
> this.

I've realized why this won't work. The problem is that ACCEPT may occur
in branches that are not scanned. It needs far too much analysis.


When computing the minimum length, the code will skip the group
altogether, because it has a minimum repeat of 0. It will end up with a
minimum length of 4, which of course is wrong.


Philip Hazel