Its the binding operator =~ which tells you that the RHS is a regex.

The m is optional, if its clearly supposed to be a regex.

IIRC are single quoted regexes documented to be taken literally, i.e. w/o variable interpolation.

edit

Indeed, see perlop

If "'" is the delimiter, no interpolation is performed on the PATTERN. 

Cheers Rolf

( addicted to the Perl Programming Language)

In reply to Re: Misreading m// documentation by LanX
in thread Misreading m// documentation by QM

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