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quadruple_of_list                                                (Lib)
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quadruple_of_list : 'a list -> 'a * 'a * 'a * 'a

SYNOPSIS
Turns a four-element list into a quadruple.

DESCRIBE
{quadruple_of_list [x1, x2, x3, x4]} returns {(x1, x2, x3, x4)}.

FAILURE
Fails if applied to a list that is not of length 4.

SEEALSO
Lib.singleton_of_list, Lib.pair_of_list, Lib.triple_of_list.

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