[Caml-list] Ppx_deriving and plugins for plugins (aka metaplugins)

[Kakadu <kakadu.hafanana@gmail.com>]

Salut, fellas

Let's say I want to create a few derivers which should generate two
parts of code:
1) specific for this family of derivers;
2) specific for concrete deriver.
For example

[@@deriving der_family { deriver1; deriver2 }]

should generate

(* XXX  code specific for family *)
(* ZZZ1 code which relies on XXX and which is specific for deriver1 *)
(* ZZZ2 code which relies on XXX and which is specific for deriver2 *)

And  [@@deriving der_family { deriver1}] should generate

(* XXX  code specific for family *)
(* YYY code which relies on XXX and which is specific for deriver1 *)

This approach should work well until I wish to support [@@deriving
der_family { deriver3 }] as a separate project. AFAIU, at the moment
ppx_deriving chooses plugin by it's exported name (i.e. der_family in
[@@deriving der_family { deriver3 }] ) but it seems that I need some
parametrization over deriver parameters.

Is it already supported? Is it easy to implement? Or I should do this
in a more straightforward manner?

Happy hacking,
Kakadu