A possibly useful addendum to the excellent guidance above( if you were to break up your regex to find a series of partial matches): perlvar and seek down for '$`', the postmatch variable.
The string following whatever was matched by the last successful pattern match (not counting any matches hidden within a BLOCK or eval() enclosed by the current BLOCK).
...

The use of this variable anywhere in a program imposes a considerable performance penalty on all regular expression matches. To avoid this penalty, you can extract the same substring by using @-. Starting with Perl 5.10, you can use the

match flag and the ${^POSTMATCH} variable to do the same thing for particular match operations.

This variable is read-only and dynamically-scoped.

See also ${^POSTMATCH} for a way to avoid the performace penalty.

In reply to Re: How to find where regex did not match across the line by ww
in thread How to find where regex did not match across the line by Anonymous Monk

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