Parameter Create.B

type ('p, 'q, +'r) t

The abstract type of monad with three parameters, two phantom types and a return type.

val return : 'r -> ('p, 'q, 'r) t

Define return a to apply a to the bound function.

val bind : ('p, 'q, 'a) t -> ('a -> ('p, 'q, 'b) t) -> ('p, 'q, 'b) t

Define bind m f to apply the value returned by m to the function f to obtain the result monad.

val mapping : [ `Default | `Special of ('p, 'q, 'a) t -> f:('a -> 'b) -> ('p, 'q, 'b) t ]

Define mapping to define the `map` operator either as the default fun a -> return (f a) or as some other special map function.

val product : [ `Default | `Special of ('p, 'q, 'a) t -> ('p, 'q, 'b) t -> ('p, 'q, 'a * 'b) t ]

Define product to select the `product` operator to be either fun a b -> bind a (fun r1 -> bind b (fun r2 -> return (r1, r2))) or some other special function.