std::integer_sequence for Hana.
std::integer_sequences are equal if and only if they have the same number of elements, and if corresponding elements compare equal. The types of the elements held in both
integer_sequences may be different, as long as they can be compared.
integer_sequenceis equivalent to folding a sequence of
std::integral_constants with the corresponding types.
integer_sequenceis equivalent to iterating over a sequence of the corresponding
integer_sequenceis equivalent to searching through the corresponding sequence of