Duals

Duals.fs

// Setters and getters
type Getter<'a> = unit -> 'a
type Setter<'a> = 'a -> unit

// An Enumerator is a getter of values. An Observer is a setter of values
type Enumerator<'a> = unit -> 'a
type Observer<'a> = 'a -> unit

// An Enumerable is a getter of Enumerators. An Observable is a setter of Observers
type Enumerable<'a> = unit -> Enumerator<'a>
type Observable'<'a> = Observer<'a> -> unit

// An Enumerable is a getter - getter. An Observer is a setter - setter
type Enumerable'<'a> = unit -> (unit -> 'a)
type Observable<'a> = ('a -> unit) -> unit