#. check the number of characters before the first "_" (underscore). #. If it's return only two characters, then get the string untill it reach the second "_"(underscore)
Okay, well because you are looking for anything that is not an underscore, then a negated character class is probably the way to go. Something like this: 
    if (/^([^_]{2}_[^_]+)_/) {
        print $1;
    }

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else if more than 2 characters then it must be a targetted pattern
Sorry, but I don't get that. What is a "targetted pattern"?

I guess i can't able to use the "\w" (word) pattern, because it will take the whole string as a word.
Yes and no. It's okay, because you are limiting it to only the first two characters with {2}. But it's probably not okay because \w will also match an underscore. So \w{2} would match something like "_a", which I'm pretty sure you don't want.

Cheers,
Darren :)

In reply to Re^3: Regular Expression - pattern matching by McDarren
in thread Regular Expression - pattern matching by kulls

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