OPERATION (preface.Preface_specs.Foldable.OPERATION)

type 'a t

The type held by Foldable.

val reduce : (module Monoid.CORE with type t = 'm) -> 'm t -> 'm

Reduce a Foldable using combine of the given monoid.

val fold_map : 
  (module Monoid.CORE with type t = 'm) ->
  ('a -> 'm) ->
  'a t ->
  'm

Same of CORE.fold_map' but using a monoid module instead of giving explicitly neutral and combine.

val fold_left : ('a -> 'b -> 'a) -> 'a -> 'b t -> 'a

Same of List.fold_left for Foldable.

val for_all : ('a -> bool) -> 'a t -> bool

Checks if all elements of the Foldable satisfy the given predicate.

val exists : ('a -> bool) -> 'a t -> bool

Checks if at least on element of the Foldable satisfy the given predicate.

val length : 'a t -> int

Count the number of elements in the Foldable.