type t

class type implementation = object
  method enumerate : Context.t -> (Handle.t, Concepts.Condition.condition) result
end

val make : #implementation -> Handle.protocol
val from : Handle.t -> t Handle.interface option

val require : Handle.t -> (t Handle.interface, Concepts.Condition.condition) result

val enumerate :
  t Handle.interface -> Context.t -> (Handle.t, Concepts.Condition.condition) result