Plugin (ppx_repr.Ppx_repr_lib.Meta

Module Meta_deriving.Plugin

A Plugin.t is a pair of functions that extend a representable type with specialised generic operations: one to supply the implementation of the specialistion, and one to supply its type.

For instance, the generic operation equal : 'a Repr.t -> 'a -> 'a -> equal could be packaged as the following plugin:

create ~intf:(fun loc t -> [%type: [%t t] -> [%t t] -> bool]) ~impl:(fun loc t -> [%expr Repr.unstage (Repr.equal [%e t])])

That is:

given some type t, its equality function has type t -> t -> bool,

given a runtime representation of t, we can derive an equality function via Repr.equal.

type t

val create : 
  ?type_name:[ `before | `after ] ->
  impl:(Ppxlib.location -> Ppxlib.expression -> Ppxlib.expression) ->
  intf:(Ppxlib.location -> Ppxlib.core_type -> Ppxlib.core_type) ->
  string ->
  t

val derive_str : 
  t ->
  loc:Ppxlib.location ->
  type_name:string ->
  params:string list ->
  expr:Ppxlib.expression ->
  Ppxlib.structure_item

val derive_sig : 
  t ->
  loc:Ppxlib.location ->
  type_name:string ->
  params:Ppxlib.core_type list ->
  ctyp:Ppxlib.core_type ->
  Ppxlib.signature_item

val defaults : t list

Default set of plugins, using the generic operations provided by Repr.