$ is a zero-width match, it does not consume a \n; 

[rick@ry ~]$ perl -e 'use strict; printf "%s\n", "ab\nab\n" =~ /^ab$ab
+$/m'
Global symbol "$ab" requires explicit package name (did you forget to 
+declare "my $ab"?) at -e line 1.
Execution of -e aborted due to compilation errors.
[rick@ry ~]$

[download]

Try adding the 'use strict;' to your other examples to see what they are really doing.

In reply to Re: Regex bug? matching multiple newline with /m by tybalt89
in thread Regex bug? matching multiple newline with /m by NERDVANA

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