Delay.Tinclude Collection.Basicval return : 'a -> 'a treturn x creates a singleton container holding x
val fold :
'a t ->
init:'s ->
f:('s -> 'a -> ('s -> 'r) -> 'r) ->
('s -> 'r) ->
'rfold xs ~init:s ~f a delayed fold implementation. It is the same as a regular fold except that function f accepts an extra continuation argument, and the fold expression returns a continuation.