http://www.perlmonks.org?node_id=1018886


in reply to Re^2: A regex that only matches at offset that are multiples of a given N?
in thread A regex that only matches at offset that are multiples of a given N?

I can't find anything about that in perlre.

perlre is not exactly optimized for quickly finding out the meaning of a specific regex construct.

Use perlreref for that.