original.name="Property_Invalid_4"
js.execute.ignore=true
======
>>> main.whiley
property contains(int[] xs, int x) -> bool:
   return some { i in 0..|xs| | xs[i] == x }

function id(int[] xs, int x, int y) -> (int[] ys)
requires contains(xs,y)
ensures contains(ys,x):
    return xs

public export method test():
   assume id([1,2,3],1,2) == [1,2,3]
   assume id([1,2,3],4,1) == [1,2,3]
---
E701 main.whiley 11,10:24
E717 main.whiley 7,4:12