The lexicographic order supported by the provided order. There is no constraint on the relative lengths of the lists.
true iff the given lists have the same length and content with respect to the given equality function.
filter_map f l applies
f to every element of
l, filters out the
None elements and returns the list of the arguments of the
If all elements of the given list are
Some _ then
Some xs is returned with the
xs being the contents of those
Somes, with order preserved. Otherwise return
let r1, r2 = map2_prefix f l1 l2 If
l1 is of length n and
l2 = h2 @ t2 with h2 of length n, r1 is
List.map2 f l1 h1 and r2 is t2.