original.name="Property_Valid_10"
======
>>> main.whiley
// This benchmark was created specifically to test recursive
// properties.

// A recursive property capturing the concept of
// the sum of an array
property sum(int[] arr, int i, int s) -> (bool r):
    return (i >= 0 && i < |arr| && sum(arr,i+1,s-arr[i])) ||
           (i >= |arr| && s == 0)

public export method test():
    //
    assert sum([],0,0)
    //
    assert sum([0],0,0)
    //
    assert sum([0,1],0,1)
    //
    assert sum([1,2,3],0,6)
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