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From: sln on 15 Jun 2010 17:16
On Tue, 15 Jun 2010 14:07:01 -0700, sln(a)netherlands.com wrote:

>On Sun, 13 Jun 2010 07:41:06 -0700 (PDT), Peng Yu <pengyu.ut(a)gmail.com> wrote:
>
>>If I only have a small number of patterns(say 3), I can just spell out
>>the matching code as below.
>>
>>grep {/$pattern1$/ or /$pattern2$/ or /$pattern3$/} @array;
>>
>>But if I have @patterns with many patterns that I want grep, the above
>>way doesn't work. I'm wondering what is the best way to grep many
>>patterns.
>
>Late to the thread, you have some good potential solutions by now.
>
>I just want to make a correction to your statement.
>If you have @patterns, it is indeed possible to spell it out and it
>does work:
>
>grep {/$pattern[1]$/ or /$pattern[2]$/ or /$pattern[3]$/} @array;
>
>I don't buy into the propaganda that @patterns are usefull.
>Here's why.
>
>When you split up a real regular expression, those with quantifiers,
>groups, and modifiers, the potential for disaster increases exponentially.
>Throwing them into "strings" to be dynamically compiled is another problem.
>Then there's that dynamic string problem.
>
>The faq's give the simplest of simple examples and are not real world.
>Multi-part regular expressions are fraught with danger in the hands of the novice
>(hell, even the experts).
>
>So, be sure to put this note in the book you are having everybody write for you.
>Sorry, no code examples, check the faq.
>

Oh, btw, grep() sucks. It can't be stopped whence you found what you need.
So don't use it for that. Its just a filter (that can't be stopped).
Put that in your book.

-sln
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