http://www.perlmonks.org?node_id=467941


in reply to old obfu tricks revealed

Ok, tonight's trick simply illustrates the principle of replacing the standard '/' separator in substitutions with other characters. It's a simple and well known trick, but can be used pretty effectively in some instances. Here goes:
$_ = "Sello World\n"; # think about alternative separators s'S'H's; print; # Deparse and compare the difference in the next two s=>o=>O=>o; print; s,o,O,o; print; # and now, for the mystery... sub s { ("x","y","z"); } s()[0]; print;
The 'mystery' has nothing to do with mixing separators or that you can use 4 instead of three, that's pretty simple stuff... it's why it replaces anything at all, much less the character it does. Happy obfu-writing!

-- So prophesied the shakespearean monkeys, and so it shall be.