jacobm

type DSL<'next> =
    | Get of string * (string -> 'next)
    | Set of string * string * 'next
    | End
    with static member fmap f = function
                | Get (k, c)    -> Get (k, f << c)
                | Set (k, v, c) -> Set (k, v, f c)
                | End           -> End

type FreeDSL<'a> =