Typically, the word boundary anchor \b works well in these cases: 
    if($line =~ /\bfor\(/) { 
       # ...
    }

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It will also match "(for(" and ";for(" which is a very common requirement for parsing programming languages. Speaking of which, if you are trying to parse perl or parts of it, check out PPI.

In reply to Re: RegEx Beginning of line or whitespace match by saintmike
in thread RegEx Beginning of line or whitespace match by THRAK

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