original.name="Property_Invalid_8"
js.execute.ignore=true
======
>>> main.whiley
property nat(int x) -> bool:
   return x >= 0
property pos(int x) -> bool:
   return x > 0

type nat is (int x) where nat(x)
type pos is (int x) where pos(x)

function f1(pos x) -> (nat y):
    return (nat) x

function f2(nat x) -> (pos y):
    return (pos) x

public export method test():
   assume f1(1) == 1
   assume f2(0) == 0
---
E702 main.whiley 13,11:17
E717 main.whiley 13,4:17