package travesty

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Module type
Class type

Demotes an arity-2 monad M to an arity-1 one, fixing its second type to be B.t.


module M : Base.Monad.S2
module B : Base.T


val (>>=) : ('a, B.t) M.t -> ('a -> ('b, B.t) M.t) -> ('b, B.t) M.t

t >>= f returns a computation that sequences the computations represented by two monad elements. The resulting computation first does t to yield a value v, and then runs the computation returned by f v.

val (>>|) : ('a, B.t) M.t -> ('a -> 'b) -> ('b, B.t) M.t

t >>| f is t >>= (fun a -> return (f a)).

module Monad_infix : sig ... end
val bind : ('a, B.t) M.t -> f:('a -> ('b, B.t) M.t) -> ('b, B.t) M.t

bind t ~f = t >>= f

val return : 'a -> ('a, B.t) M.t

return v returns the (trivial) computation that returns v.

val map : ('a, B.t) M.t -> f:('a -> 'b) -> ('b, B.t) M.t

map t ~f is t >>| f.

val join : (('a, B.t) M.t, B.t) M.t -> ('a, B.t) M.t

join t is t >>= (fun t' -> t').

val ignore_m : ('a, B.t) M.t -> (unit, B.t) M.t

ignore_m t is map t ~f:(fun _ -> ()). ignore_m used to be called ignore, but we decided that was a bad name, because it shadowed the widely used Caml.ignore. Some monads still do let ignore = ignore_m for historical reasons.

val all : ('a, B.t) M.t list -> ('a list, B.t) M.t
val all_unit : (unit, B.t) M.t list -> (unit, B.t) M.t

Like all, but ensures that every monadic value in the list produces a unit value, all of which are discarded rather than being collected into a list.

module Let_syntax : sig ... end

These are convenient to have in scope when programming with a monad:


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