original.name="TypeEquals_Valid_47"
======
>>> main.whiley


type nat is (int n) where n >= 0

type iorarr is int | int[]

function f(iorarr x) -> int:
    if x is int[] | nat:
        return 0
    else:
        return x

public export method test() :
    assume f(1) == 0
    assume f(-1) == -1
    assume f([1, 2, 3]) == 0

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