gistfile1.txt

let f(h as (Number) -> Number, x as Number)
  // h should take a parameter. it does not, but who cares.
  let v = h(x)
  // now v should be a Number, right?
  // because we told GorillaScript up there, of course it can optimize this condition away
  if (typeof v == "number" or v instanceof Number)
    v / 1.23
  

let g()
  let x = 42
  if (x <= 2)
    1
  else
    {wat: "wat"}

alert(f(g, 2)) // NaN, obviously.