type t

class type implementation = object
  method indexes : string list
  method lookup : string -> Concepts.Value.value -> (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 indexes : t Handle.interface -> string list

val lookup :
  t Handle.interface ->
  string ->
  Concepts.Value.value ->
  (Handle.t, Concepts.Condition.condition) result