val gt_param :
string ->Ppxlib__.Import.expression optionPpxlib.Deriving.Args.param
val r :
(Ppxlib__.Import.expression,
(Ppxlib__.Import.longident * Ppxlib__.Import.expression) list->(Ppxlib__.Import.longident * Ppxlib__.Import.expression) list option,
(Ppxlib__.Import.longident * Ppxlib__.Import.expression) list option)Ppxlib__.Ast_pattern.t