Module type Parameter_sig.Value_datatype

module type Value_datatype = sig .. end

Signature of the optional value associated to the key and required to build map parameters.


include Datatype.S
type key 
val of_string : key:key ->
prev:t option -> string option -> t option

key is the key associated to this value, while prev is the previous value associated to this key (if any). The optional string is None if there is no value associated to the key, and Some v (potentially v =
      ""
) otherwise.

val to_string : key:key -> t option -> string option

key is the key associated to this value. The optional string is None if there is no value associated to the key, and Some v (potentially v =
    ""
) otherwise.