Unless I'm understanding your intentions wrong, that's the purpose of \b.

  Example: m/\bChi_2\b/

I don't think the underscore will cause you problems within the defined \b \b but I'm sure I'll be corrected shortly if I'm wrong. :)

UPDATE: 1.20.2011 1:30PM
• Through help in the chatterbox and "Mastering Regular Expressions" pg. 89, I learned that \w has included _ since Perl 2. So /\bChi_2\b/ will not match.


"...the adversities born of well-placed thoughts should be considered mercies rather than misfortunes." — Don Quixote

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In reply to Re: Defining Characters in Word Boundary? by luis.roca
in thread Defining Characters in Word Boundary? by iaw4

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