original.name="Property_Valid_8"
======
>>> main.whiley
property nat(int x) -> (bool r):
return x >= 0
type nat is (int x) where nat(x)
function id(nat x) -> (nat y):
return x
public export method test():
assume id(0) == 0
assume id(1) == 1
assume id(2) == 2
---