I just came across this fun Perl function that I can't think of a (good) use for, but have to share.
In the Scalar::Util module is the function dualvar:
Returns a scalar that has the value NUM in a numeric context and the value STRING in a string context.
$foo = dualvar 10, "Hello"; $num = $foo + 2; # 12 $str = $foo . " world"; # Hello world
Using that in the right place could lead a future programmer down some fun debugging paths!