http://qs321.pair.com?node_id=643870


in reply to Re^3: How to swap rows with columns?
in thread How to swap rows with columns?

I'm hoping this node helps other monks who may not have unraveled "_'_".

You didn't say what it was. ' is Perl4 for ::. It's still supported in Perl5, by it shouldn't be used in new code. This is documented in the second paragraph of perlmod.

$_::_ is just some arbitrary variable. Despite it's appearance to $_, it's not a special variable.