triple_of_list
Lib.triple_of_list : 'a list -> 'a * 'a * 'a
Turns a three-element list into a triple.
triple_of_list [x, y, z] returns (x, y, z).
Failure
Fails if applied to a list that is not of length 3.
See also
Lib.singleton_of_list,
Lib.pair_of_list,
Lib.quadruple_of_list