(* Title: HOL/Tools/typecopy_package.ML
ID: $Id$
Author: Florian Haftmann, TU Muenchen
Introducing copies of types using trivial typedefs; datatype-like abstraction.
*)
signature TYPECOPY_PACKAGE =
sig
type info = {
vs: (string * sort) list,
constr: string,
typ: typ,
inject: thm,
proj: string * typ,
proj_def: thm
}
val add_typecopy: bstring * string list -> typ -> (bstring * bstring) option
-> theory -> (string * info) * theory
val get_typecopies: theory -> string list
val get_typecopy_info: theory -> string -> info option
val interpretation: (string * info -> theory -> theory) -> theory -> theory
val get_spec: theory -> string -> (string * sort) list * (string * typ list) list
val get_eq: theory -> string -> thm
val print_typecopies: theory -> unit
val setup: theory -> theory
end;
structure TypecopyPackage: TYPECOPY_PACKAGE =
struct
(* theory data *)
type info = {
vs: (string * sort) list,
constr: string,
typ: typ,
inject: thm,
proj: string * typ,
proj_def: thm
};
structure TypecopyData = TheoryDataFun
(
type T = info Symtab.table;
val empty = Symtab.empty;
val copy = I;
val extend = I;
fun merge _ = Symtab.merge (K true);
);
fun print_typecopies thy =
let
val tab = TypecopyData.get thy;
fun mk (tyco, { vs, constr, typ, proj = (proj, _), ... } : info) =
(Pretty.block o Pretty.breaks) [
Sign.pretty_typ thy (Type (tyco, map TFree vs)),
Pretty.str "=",
(Pretty.str o Sign.extern_const thy) constr,
Sign.pretty_typ thy typ,
Pretty.block [Pretty.str "(", (Pretty.str o Sign.extern_const thy) proj, Pretty.str ")"]];
in
(Pretty.writeln o Pretty.block o Pretty.fbreaks)
(Pretty.str "type copies:" :: map mk (Symtab.dest tab))
end;
val get_typecopies = Symtab.keys o TypecopyData.get;
val get_typecopy_info = Symtab.lookup o TypecopyData.get;
(* interpretation *)
structure TypecopyInterpretation = InterpretationFun(type T = string val eq = op =);
fun interpretation interp = TypecopyInterpretation.interpretation
(fn tyco => fn thy => interp (tyco, (the o get_typecopy_info thy) tyco) thy);
(* add a type copy *)
local
fun gen_add_typecopy prep_typ (raw_tyco, raw_vs) raw_ty constr_proj thy =
let
val ty = prep_typ thy raw_ty;
val vs = AList.make (the_default HOLogic.typeS o AList.lookup (op =) (typ_tfrees ty)) raw_vs;
val tac = Tactic.rtac UNIV_witness 1;
fun add_info tyco ( { abs_type = ty_abs, rep_type = ty_rep, Abs_name = c_abs,
Rep_name = c_rep, Abs_inject = inject,
Abs_inverse = inverse, ... } : TypedefPackage.info ) thy =
let
val exists_thm =
UNIV_I
|> Drule.instantiate' [SOME (ctyp_of thy (Logic.varifyT ty_rep))] [];
val inject' = inject OF [exists_thm, exists_thm];
val proj_def = inverse OF [exists_thm];
val info = {
vs = vs,
constr = c_abs,
typ = ty_rep,
inject = inject',
proj = (c_rep, ty_abs --> ty_rep),
proj_def = proj_def
};
in
thy
|> (TypecopyData.map o Symtab.update_new) (tyco, info)
|> TypecopyInterpretation.data tyco
|> pair (tyco, info)
end
in
thy
|> setmp TypedefPackage.quiet_mode true
(TypedefPackage.add_typedef_i false (SOME raw_tyco) (raw_tyco, map fst vs, NoSyn)
(HOLogic.mk_UNIV ty) (Option.map swap constr_proj)) tac
|-> (fn (tyco, info) => add_info tyco info)
end;
in
val add_typecopy = gen_add_typecopy Sign.certify_typ;
end;
(* equality function equation and datatype specification *)
fun get_eq thy tyco =
(#inject o the o get_typecopy_info thy) tyco;
fun get_spec thy tyco =
let
val SOME { vs, constr, typ, ... } = get_typecopy_info thy tyco
in (vs, [(constr, [typ])]) end;
(* interpretation for projection function code *)
fun add_project (_, {proj_def, ...} : info) = Code.add_default_func proj_def;
val setup = TypecopyInterpretation.init #> interpretation add_project;
end;