major reorganization/simplification of HOLCF type classes:
removed profinite/bifinite classes and approx function;
universal domain uses approx_chain locale instead of bifinite class;
ideal_completion locale does not use 'take' functions, requires countable basis instead;
replaced type 'udom alg_defl' with type 'sfp';
replaced class 'rep' with class 'sfp';
renamed REP('a) to SFP('a);
(* Title: HOLCF/Tools/repdef.ML
Author: Brian Huffman
Defining representable domains using algebraic deflations.
*)
signature REPDEF =
sig
type rep_info =
{ emb_def: thm, prj_def: thm, sfp_def: thm, SFP: thm }
val add_repdef: bool -> binding option -> binding * (string * sort) list * mixfix ->
term -> (binding * binding) option -> theory ->
(Typedef.info * Pcpodef.cpo_info * Pcpodef.pcpo_info * rep_info) * theory
val repdef_cmd: (bool * binding) * (binding * (string * string option) list * mixfix) * string
* (binding * binding) option -> theory -> theory
end;
structure Repdef :> REPDEF =
struct
open HOLCF_Library;
infixr 6 ->>;
infix -->>;
(** type definitions **)
type rep_info =
{ emb_def: thm, prj_def: thm, sfp_def: thm, SFP: thm };
(* building types and terms *)
val udomT = @{typ udom};
val sfpT = @{typ sfp};
fun emb_const T = Const (@{const_name emb}, T ->> udomT);
fun prj_const T = Const (@{const_name prj}, udomT ->> T);
fun sfp_const T = Const (@{const_name sfp}, Term.itselfT T --> sfpT);
fun mk_cast (t, x) =
capply_const (udomT, udomT)
$ (capply_const (sfpT, udomT ->> udomT) $ @{const cast} $ t)
$ x;
(* manipulating theorems *)
(* proving class instances *)
fun declare_type_name a =
Variable.declare_constraints (Logic.mk_type (TFree (a, dummyS)));
fun gen_add_repdef
(prep_term: Proof.context -> 'a -> term)
(def: bool)
(name: binding)
(typ as (tname, raw_args, mx) : binding * (string * sort) list * mixfix)
(raw_defl: 'a)
(opt_morphs: (binding * binding) option)
(thy: theory)
: (Typedef.info * Pcpodef.cpo_info * Pcpodef.pcpo_info * rep_info) * theory =
let
val _ = Theory.requires thy "Representable" "repdefs";
(*rhs*)
val tmp_ctxt =
ProofContext.init_global thy
|> fold (Variable.declare_typ o TFree) raw_args;
val defl = prep_term tmp_ctxt raw_defl;
val tmp_ctxt = tmp_ctxt |> Variable.declare_constraints defl;
val deflT = Term.fastype_of defl;
val _ = if deflT = @{typ "sfp"} then ()
else error ("Not type sfp: " ^ quote (Syntax.string_of_typ tmp_ctxt deflT));
(*lhs*)
val lhs_tfrees = map (ProofContext.check_tfree tmp_ctxt) raw_args;
val lhs_sorts = map snd lhs_tfrees;
val full_tname = Sign.full_name thy tname;
val newT = Type (full_tname, map TFree lhs_tfrees);
(*morphisms*)
val morphs = opt_morphs
|> the_default (Binding.prefix_name "Rep_" name, Binding.prefix_name "Abs_" name);
(*set*)
val in_defl = @{term "in_sfp :: udom => sfp => bool"};
val set = HOLogic.Collect_const udomT $ Abs ("x", udomT, in_defl $ Bound 0 $ defl);
(*pcpodef*)
val tac1 = rtac @{thm CollectI} 1 THEN rtac @{thm bottom_in_sfp} 1;
val tac2 = rtac @{thm adm_mem_Collect_in_sfp} 1;
val ((info, cpo_info, pcpo_info), thy) = thy
|> Pcpodef.add_pcpodef def (SOME name) typ set (SOME morphs) (tac1, tac2);
(*definitions*)
val Rep_const = Const (#Rep_name (#1 info), newT --> udomT);
val Abs_const = Const (#Abs_name (#1 info), udomT --> newT);
val emb_eqn = Logic.mk_equals (emb_const newT, cabs_const (newT, udomT) $ Rep_const);
val prj_eqn = Logic.mk_equals (prj_const newT, cabs_const (udomT, newT) $
Abs ("x", udomT, Abs_const $ mk_cast (defl, Bound 0)));
val sfp_eqn = Logic.mk_equals (sfp_const newT,
Abs ("x", Term.itselfT newT, defl));
val name_def = Binding.suffix_name "_def" name;
val emb_bind = (Binding.prefix_name "emb_" name_def, []);
val prj_bind = (Binding.prefix_name "prj_" name_def, []);
val sfp_bind = (Binding.prefix_name "sfp_" name_def, []);
(*instantiate class rep*)
val lthy = thy
|> Class.instantiation ([full_tname], lhs_tfrees, @{sort sfp});
val ((_, (_, emb_ldef)), lthy) =
Specification.definition (NONE, (emb_bind, emb_eqn)) lthy;
val ((_, (_, prj_ldef)), lthy) =
Specification.definition (NONE, (prj_bind, prj_eqn)) lthy;
val ((_, (_, sfp_ldef)), lthy) =
Specification.definition (NONE, (sfp_bind, sfp_eqn)) lthy;
val ctxt_thy = ProofContext.init_global (ProofContext.theory_of lthy);
val emb_def = singleton (ProofContext.export lthy ctxt_thy) emb_ldef;
val prj_def = singleton (ProofContext.export lthy ctxt_thy) prj_ldef;
val sfp_def = singleton (ProofContext.export lthy ctxt_thy) sfp_ldef;
val type_definition_thm =
MetaSimplifier.rewrite_rule
(the_list (#set_def (#2 info)))
(#type_definition (#2 info));
val typedef_thms =
[type_definition_thm, #below_def cpo_info, emb_def, prj_def, sfp_def];
val thy = lthy
|> Class.prove_instantiation_instance
(K (Tactic.rtac (@{thm typedef_rep_class} OF typedef_thms) 1))
|> Local_Theory.exit_global;
(*other theorems*)
val sfp_thm' = Thm.transfer thy sfp_def;
val (SFP_thm, thy) = thy
|> Sign.add_path (Binding.name_of name)
|> Global_Theory.add_thm
((Binding.prefix_name "SFP_" name,
Drule.zero_var_indexes (@{thm typedef_SFP} OF [sfp_thm'])), [])
||> Sign.restore_naming thy;
val rep_info =
{ emb_def = emb_def, prj_def = prj_def, sfp_def = sfp_def, SFP = SFP_thm };
in
((info, cpo_info, pcpo_info, rep_info), thy)
end
handle ERROR msg =>
cat_error msg ("The error(s) above occurred in repdef " ^ quote (Binding.str_of name));
fun add_repdef def opt_name typ defl opt_morphs thy =
let
val name = the_default (#1 typ) opt_name;
in
gen_add_repdef Syntax.check_term def name typ defl opt_morphs thy
end;
fun repdef_cmd ((def, name), (b, raw_args, mx), A, morphs) thy =
let
val ctxt = ProofContext.init_global thy;
val args = map (apsnd (Typedecl.read_constraint ctxt)) raw_args;
in snd (gen_add_repdef Syntax.read_term def name (b, args, mx) A morphs thy) end;
(** outer syntax **)
val repdef_decl =
Scan.optional (Parse.$$$ "(" |--
((Parse.$$$ "open" >> K false) -- Scan.option Parse.binding ||
Parse.binding >> (fn s => (true, SOME s)))
--| Parse.$$$ ")") (true, NONE) --
(Parse.type_args_constrained -- Parse.binding) --
Parse.opt_mixfix -- (Parse.$$$ "=" |-- Parse.term) --
Scan.option (Parse.$$$ "morphisms" |-- Parse.!!! (Parse.binding -- Parse.binding));
fun mk_repdef ((((((def, opt_name), (args, t)), mx), A), morphs)) =
repdef_cmd ((def, the_default t opt_name), (t, args, mx), A, morphs);
val _ =
Outer_Syntax.command "repdef" "HOLCF definition of representable domains" Keyword.thy_decl
(repdef_decl >>
(Toplevel.print oo (Toplevel.theory o mk_repdef)));
end;