module Pa_deriving_Json:sig
..end
type typ = .. deriving (Json)
with generate
module Json_typ : sig
type a = typ
val to_string : a -> string
val from_string : string -> a
...
end
val register_predefs : Pa_deriving_common.Type.qname -> Pa_deriving_common.Type.qname -> unit
register_predefs typeA typeB
tells the syntax extension
that typeB
is an alias for typeA
.
The extension syntax will then use the deriving_json implementation
of typeB
in place of typeA
's one.
Important note: TypeB does NOT HAVE TO actually exists.
In practive, you may need to use this in the following cases: