The question is not so much 'What Can't Regexp Do?', but when shouldn't you use it.
There are times when processing strings where it is easier and faster to use a substr
to grab what you need from input. This is especially true if you know that the length
of the input elements does not change (ie a fixed-width flat text file...). I guess the
analogy would be that if you wanted to dig postholes for a fence, you could use a shovel,
which is powerful and has many different ways to use, but is not as efficient as a posthole
digger. Don't get me wrong, I love regexps, but sometimes, they are not the best tool for
the job. :)

In reply to Re: What can regular expressions NOT do? by buzzcutbuddha
in thread What can regular expressions NOT do? by kryten

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