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Re: regrepeat()

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Father Chrysostomos
January 1, 2018 01:21
Re: regrepeat()
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Karl Williamson wrote:
> It turns out that these cases can be sped up dramatically if what we are
> matching is a long string of 'a's in a row.  We simply load a word with
> 4 or 8 a's and look at the string a word-at-a-time, which uses 1/4 or
> 1/8 the number of instructions.  By using a mask, this can be extended
> to work for
>   [aA]+
> as well.  The code in each case is just over 20 lines of C.
> My question is, does this happen often enough in real life to justify
> the extra code?

I think so.  People also parse plain text with rows of hyphens, etc.

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