original.name="ConstrainedList_Valid_25"
======
>>> main.whiley


function indexOf(int[] list, int index) -> int
requires all { i in 0..|list| | list[i] >= 0 }
requires index >= 0 && index < |list|:
    return list[index]

public export method test() :
    int[] items = [5, 4, 6, 3, 7, 2, 8, 1]
    int i = 0
    while i < |items|
        where i >= 0
        where all { k in 0..|items| | items[k] >= 0 }:
        assume indexOf(items,i) == items[i]
        i = i + 1

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