... why did you use the m modifier?

This is in line with the recommendations of TheDamian's Perl Best Practices (PBP) for regexes. The /m regex modifier causes  ^ $ regex operators also to match after/before embedded newlines. The invariable use of /m and the /s (dot-matches-all, including newlines) modifiers reduces the number of degrees of freedom enjoyed by these operators. In turn, this reduces potential maintenance headaches (I'll show you my scars sometime) and the general brain-hurt associated with regexes.

The PBP recommendations in general and those for regexes in particular are controversial. (See especially BrowserUk for vigorous counter-argument; also, I think, the JavaFan.) I find many, perhaps most, of the recommendations to have compelling arguments in their favor and I rigorously (dare I say blindly?) use those pertaining to regexes.

In reply to Re^3: Match zero times in regex by AnomalousMonk
in thread Match zero times in regex by SomeNetworkGuy

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