Hello, I'd like to announce the release of PEC, a push style event combinator.
PEC : https://github.com/osiire/Pec This small module(about 350 LOC) provides - a composable event. - map, choose, never, join and several useful functions. - immediate reactions corresponds sending data to events. - no memory leaks. I think PEC is useful to write event driven systems. The signature is as follows. type 'a event (** [make ()] makes a new event and sender function.*) val make : unit -> 'a event * ('a -> unit) val map : ('a -> 'b) -> 'a event -> 'b event (** [choose l] is a event which will be raised when one of specified events occurred. *) val choose : 'a event list -> 'a event val never : 'a event (** [join ee] is a event which will be raised when a inner event occurred. "Inner event" is a event comes from outer event [ee]. *) val join : 'a event event -> 'a event (** [bind e f] is [join (map f e)] *) val bind : 'a event -> ('a -> 'b event) -> 'b event val scan : ('a -> 'b -> 'a) -> 'a -> 'b event -> 'a event val filter : ('a -> bool) -> 'a event -> 'a event val filter_map : ('a -> 'b option) -> 'a event -> 'b event val zip : 'a event -> 'b event -> ('a * 'b) event val take_while : ('a -> bool) -> 'a event -> 'a event val take_while_in : ('a -> bool) -> 'a event -> 'a event val take_n : int -> 'a event -> 'a event val once : 'a event -> 'a event val drop_while : ('a -> bool) -> 'a event -> 'a event val drop_n : int -> 'a event -> 'a event val delay : int -> 'a event -> 'a event val pairwise : 'a event -> ('a * 'a) event (** [subscribe f e] attaches the [f] to the specified event. The [f] will be called when the [e] will occurred. *) val subscribe : ('a -> unit) -> 'a event -> unit (** [value e] returns a reference cell which store a latest value *) val value : 'a -> 'a event -> 'a ref (** [run ()] runs PEC event system and returns a number of queuing size of sended data. *) val run : unit -> int e.g. Using PEC, you can write a drag event from mouse events like this. let (+>) f g = g f (* E is PEC module *) let dragging mouse_down mouse_up mouse_move = E.bind mouse_down (fun dloc -> E.choose [ E.map (fun uloc -> `Drop (dloc, uloc)) mouse_up; E.map (fun mloc -> `Drag (dloc, mloc)) mouse_move; ] +> E.take_while_in (function `Drop _ -> false | _ -> true)) Regards, ogasawara -- Caml-list mailing list. Subscription management and archives: https://sympa-roc.inria.fr/wws/info/caml-list Beginner's list: http://groups.yahoo.com/group/ocaml_beginners Bug reports: http://caml.inria.fr/bin/caml-bugs
