xkcd 1537

gistfile1.txt

module Xkcd::Types {
   multi sub infix:<+>(Int $n, Str $m)       { ($n + $m.Int).Str }
   multi sub infix:<+>(Str $n, @a where !@a) { "[$n]" }
   multi sub infix:</>(Int $n, 0) is export  { NaN }
   multi sub infix:<+>(NaN, Int $n)          { class NaP {};  }
   multi sub infix:<+>("", "")               { '"+"' }
   multi sub infix:<+>(Array $a, Int $n) is export { so none(|$a) == $n }                                                               
};

import Xkcd::Types;                                                                                                                     
.perl.say for ( 2 + "2", "2" + [], (2/0), (2/0) + 2, ""+"", [1,2,3] + 2, [1,2,3] + 4);