my $result = $pattern ^ $_;

[download]
This XORs $pattern and $_ together, and stores it in $result. 
my $matches = $result =~ tr/\0//;

[download]
This counts the number of matches, and puts that into $matches.

-QM
--
Quantum Mechanics: The dreams stuff is made of

In reply to Re^3: How to use regular expression for this? by QM
in thread How to use regular expression for this? by davidz2f

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