@sig(["a"]/ H[(Num, "a")] >> "a")
def sum(xs):
    """
    sum :: Num a => [a] -> a

    The sum function computes the sum of a finite list of numbers.
    """
    return functools.reduce(operator.add, xs, 0)
dataset/ETHPy150Open billpmurphy/hask/hask/Data/List.py/sum/swapped operands of `/`