_{Jamie Balfour's}Personal blog

Finally, union types are accepted in ZPE 1.11.4. The March release known as OmegaZ will now include union return types:

function doubleNum(integer $x) : integer | real
  return $x * 2
end function
print(doubleNum(2))

It will also soon support union parameter and variable declarations which are expected in OmegaY also. This further expansion of ZPE's TYPO nudges TYPO to version 2.1. All of this new stuff has been added with almost no performance penalty at all.