An interview with Larry Wall (LinuxVoice)

The first thing I came up with:

($a,$b) ~~ :(Int, Int) or fail; $a + $b;

The `:(...)` bit is a literal signature, exactly like the ones that appear in function definitions. The `~~` "smartmatch" operator, with these operands, does a trial bind of the argument list on its left with the signature on its right.

I skipped testing the result because an Int can store arbitrarily large integers, and if all of RAM was consumed by a truly vast integer, an exception would (should) be raised by lower levels of the stack.