filter
Lib.filter : ('a -> bool) -> 'a list -> 'a list
Filters a list to the sublist of elements satisfying a predicate.
filter P l applies P to every element of l, returning a list of
those that satisfy P, in the order they appeared in the original list.
Failure
If P x fails for some element x of l.
Comments
Identical to List.filter from the Standard ML Basis Library.