author | wenzelm |
Tue, 27 Apr 2010 14:41:27 +0200 | |
changeset 36418 | 752ee03427c2 |
parent 36417 | 54bc1a44967d |
child 36419 | 7aea10d10113 |
permissions | -rw-r--r-- |
(* Title: Pure/axclass.ML Author: Markus Wenzel, TU Muenchen Type classes defined as predicates, associated with a record of parameters. Proven class relations and type arities. *) signature AX_CLASS = sig val define_class: binding * class list -> string list -> (Thm.binding * term list) list -> theory -> class * theory val add_classrel: thm -> theory -> theory val add_arity: thm -> theory -> theory val prove_classrel: class * class -> tactic -> theory -> theory val prove_arity: string * sort list * sort -> tactic -> theory -> theory type info = {def: thm, intro: thm, axioms: thm list, params: (string * typ) list} val get_info: theory -> class -> info val class_of_param: theory -> string -> class option val cert_classrel: theory -> class * class -> class * class val read_classrel: theory -> xstring * xstring -> class * class val axiomatize_class: binding * class list -> theory -> theory val axiomatize_class_cmd: binding * xstring list -> theory -> theory val axiomatize_classrel: (class * class) list -> theory -> theory val axiomatize_classrel_cmd: (xstring * xstring) list -> theory -> theory val axiomatize_arity: arity -> theory -> theory val axiomatize_arity_cmd: xstring * string list * string -> theory -> theory val instance_name: string * class -> string val declare_overloaded: string * typ -> theory -> term * theory val define_overloaded: binding -> string * term -> theory -> thm * theory val unoverload: theory -> thm -> thm val overload: theory -> thm -> thm val unoverload_conv: theory -> conv val overload_conv: theory -> conv val unoverload_const: theory -> string * typ -> string val lookup_inst_param: Consts.T -> ((string * string) * 'a) list -> string * typ -> 'a option val param_of_inst: theory -> string * string -> string val inst_of_param: theory -> string -> (string * string) option val thynames_of_arity: theory -> class * string -> string list end; structure AxClass: AX_CLASS = struct (** theory data **) (* axclass info *) type info = {def: thm, intro: thm, axioms: thm list, params: (string * typ) list}; fun make_axclass (def, intro, axioms, params): info = {def = def, intro = intro, axioms = axioms, params = params}; (* class parameters (canonical order) *) type param = string * class; fun add_param pp ((x, c): param) params = (case AList.lookup (op =) params x of NONE => (x, c) :: params | SOME c' => error ("Duplicate class parameter " ^ quote x ^ " for " ^ Pretty.string_of_sort pp [c] ^ (if c = c' then "" else " and " ^ Pretty.string_of_sort pp [c']))); (* setup data *) datatype data = Data of {axclasses: info Symtab.table, params: param list, proven_classrels: thm Symreltab.table, proven_arities: ((class * sort list) * (thm * string)) list Symtab.table, (*arity theorems with theory name*) inst_params: (string * thm) Symtab.table Symtab.table * (*constant name ~> type constructor ~> (constant name, equation)*) (string * string) Symtab.table (*constant name ~> (constant name, type constructor)*), diff_merge_classrels: (class * class) list}; fun make_data (axclasses, params, proven_classrels, proven_arities, inst_params, diff_merge_classrels) = Data {axclasses = axclasses, params = params, proven_classrels = proven_classrels, proven_arities = proven_arities, inst_params = inst_params, diff_merge_classrels = diff_merge_classrels}; structure Data = Theory_Data_PP ( type T = data; val empty = make_data (Symtab.empty, [], Symreltab.empty, Symtab.empty, (Symtab.empty, Symtab.empty), []); val extend = I; fun merge pp (Data {axclasses = axclasses1, params = params1, proven_classrels = proven_classrels1, proven_arities = proven_arities1, inst_params = inst_params1, diff_merge_classrels = diff_merge_classrels1}, Data {axclasses = axclasses2, params = params2, proven_classrels = proven_classrels2, proven_arities = proven_arities2, inst_params = inst_params2, diff_merge_classrels = diff_merge_classrels2}) = let val axclasses' = Symtab.merge (K true) (axclasses1, axclasses2); val params' = if null params1 then params2 else fold_rev (fn p => if member (op =) params1 p then I else add_param pp p) params2 params1; (*transitive closure of classrels and arity completion is done in Theory.at_begin hook*) val proven_classrels' = Symreltab.join (K #1) (proven_classrels1, proven_classrels2); val proven_arities' = Symtab.join (K (Library.merge (eq_fst op =))) (proven_arities1, proven_arities2); val classrels1 = Symreltab.keys proven_classrels1; val classrels2 = Symreltab.keys proven_classrels2; val diff_merge_classrels' = subtract (op =) classrels1 classrels2 @ subtract (op =) classrels2 classrels1 @ diff_merge_classrels1 @ diff_merge_classrels2; val inst_params' = (Symtab.join (K (Symtab.merge (K true))) (#1 inst_params1, #1 inst_params2), Symtab.merge (K true) (#2 inst_params1, #2 inst_params2)); in make_data (axclasses', params', proven_classrels', proven_arities', inst_params', diff_merge_classrels') end; ); fun map_data f = Data.map (fn Data {axclasses, params, proven_classrels, proven_arities, inst_params, diff_merge_classrels} => make_data (f (axclasses, params, proven_classrels, proven_arities, inst_params, diff_merge_classrels))); fun map_axclasses f = map_data (fn (axclasses, params, proven_classrels, proven_arities, inst_params, diff_merge_classrels) => (f axclasses, params, proven_classrels, proven_arities, inst_params, diff_merge_classrels)); fun map_params f = map_data (fn (axclasses, params, proven_classrels, proven_arities, inst_params, diff_merge_classrels) => (axclasses, f params, proven_classrels, proven_arities, inst_params, diff_merge_classrels)); fun map_proven_classrels f = map_data (fn (axclasses, params, proven_classrels, proven_arities, inst_params, diff_merge_classrels) => (axclasses, params, f proven_classrels, proven_arities, inst_params, diff_merge_classrels)); fun map_proven_arities f = map_data (fn (axclasses, params, proven_classrels, proven_arities, inst_params, diff_merge_classrels) => (axclasses, params, proven_classrels, f proven_arities, inst_params, diff_merge_classrels)); fun map_inst_params f = map_data (fn (axclasses, params, proven_classrels, proven_arities, inst_params, diff_merge_classrels) => (axclasses, params, proven_classrels, proven_arities, f inst_params, diff_merge_classrels)); val clear_diff_merge_classrels = map_data (fn (axclasses, params, proven_classrels, proven_arities, inst_params, _) => (axclasses, params, proven_classrels, proven_arities, inst_params, [])); val rep_data = Data.get #> (fn Data args => args); val axclasses_of = #axclasses o rep_data; val params_of = #params o rep_data; val proven_classrels_of = #proven_classrels o rep_data; val proven_arities_of = #proven_arities o rep_data; val inst_params_of = #inst_params o rep_data; val diff_merge_classrels_of = #diff_merge_classrels o rep_data; (* axclasses with parameters *) fun get_info thy c = (case Symtab.lookup (axclasses_of thy) c of SOME info => info | NONE => error ("No such axclass: " ^ quote c)); fun all_params_of thy S = let val params = params_of thy; in fold (fn (x, c) => if Sign.subsort thy (S, [c]) then cons x else I) params [] end; fun class_of_param thy = AList.lookup (op =) (params_of thy); (* maintain instances *) val classrel_prefix = "classrel_"; val arity_prefix = "arity_"; fun instance_name (a, c) = Long_Name.base_name c ^ "_" ^ Long_Name.base_name a; fun the_classrel thy (c1, c2) = (case Symreltab.lookup (proven_classrels_of thy) (c1, c2) of SOME thm => Thm.transfer thy thm | NONE => error ("Unproven class relation " ^ Syntax.string_of_classrel (ProofContext.init thy) [c1, c2])); fun put_trancl_classrel ((c1, c2), th) thy = let val cert = Thm.cterm_of thy; val certT = Thm.ctyp_of thy; val classes = Sorts.classes_of (Sign.classes_of thy); val classrels = proven_classrels_of thy; fun reflcl_classrel (c1', c2') = if c1' = c2' then Thm.trivial (cert (Logic.mk_of_class (TVar ((Name.aT, 0), []), c1'))) else the_classrel thy (c1', c2'); fun gen_classrel (c1_pred, c2_succ) = let val th' = ((reflcl_classrel (c1_pred, c1) RS th) RS reflcl_classrel (c2, c2_succ)) |> Drule.instantiate' [SOME (certT (TVar ((Name.aT, 0), [])))] [] |> Thm.close_derivation; in ((c1_pred, c2_succ), th') end; val new_classrels = Library.map_product pair (c1 :: Graph.imm_preds classes c1) (c2 :: Graph.imm_succs classes c2) |> filter_out (Symreltab.defined classrels) |> map gen_classrel; val needed = not (null new_classrels); in (needed, if needed then map_proven_classrels (fold Symreltab.update new_classrels) thy else thy) end; fun complete_classrels thy = let val classrels = proven_classrels_of thy; val diff_merge_classrels = diff_merge_classrels_of thy; val (needed, thy') = (false, thy) |> fold (fn rel => fn (needed, thy) => put_trancl_classrel (rel, Symreltab.lookup classrels rel |> the) thy |>> (fn b => needed orelse b)) diff_merge_classrels; in if null diff_merge_classrels then NONE else SOME (clear_diff_merge_classrels thy') end; fun the_arity thy a (c, Ss) = (case AList.lookup (op =) (Symtab.lookup_list (proven_arities_of thy) a) (c, Ss) of SOME (thm, _) => Thm.transfer thy thm | NONE => error ("Unproven type arity " ^ Syntax.string_of_arity (ProofContext.init thy) (a, Ss, [c]))); fun thynames_of_arity thy (c, a) = Symtab.lookup_list (proven_arities_of thy) a |> map_filter (fn ((c', _), (_, name)) => if c = c' then SOME name else NONE) |> rev; fun insert_arity_completions thy (t, ((c, Ss), ((th, thy_name)))) arities = let val algebra = Sign.classes_of thy; val ars = Symtab.lookup_list arities t; val super_class_completions = Sign.super_classes thy c |> filter_out (fn c1 => exists (fn ((c2, Ss2), _) => c1 = c2 andalso Sorts.sorts_le algebra (Ss2, Ss)) ars); val names = Name.invents Name.context Name.aT (length Ss); val std_vars = map (fn a => SOME (ctyp_of thy (TVar ((a, 0), [])))) names; val completions = super_class_completions |> map (fn c1 => let val th1 = (th RS the_classrel thy (c, c1)) |> Drule.instantiate' std_vars [] |> Thm.close_derivation; in ((th1, thy_name), c1) end); val arities' = fold (fn (th, c1) => Symtab.cons_list (t, ((c1, Ss), th))) completions arities; in (null completions, arities') end; fun put_arity ((t, Ss, c), th) thy = let val arity = (t, ((c, Ss), (th, Context.theory_name thy))) in thy |> map_proven_arities (Symtab.insert_list (eq_fst op =) arity #> insert_arity_completions thy arity #> #2) end; fun complete_arities thy = let val arities = proven_arities_of thy; val (finished, arities') = arities |> fold_map (insert_arity_completions thy) (Symtab.dest_list arities); in if forall I finished then NONE else SOME (map_proven_arities (K arities') thy) end; val _ = Context.>> (Context.map_theory (Theory.at_begin complete_classrels #> Theory.at_begin complete_arities)); val the_classrel_prf = Thm.proof_of oo the_classrel; val the_arity_prf = Thm.proof_of ooo the_arity; (* maintain instance parameters *) fun get_inst_param thy (c, tyco) = (case Symtab.lookup (the_default Symtab.empty (Symtab.lookup (#1 (inst_params_of thy)) c)) tyco of SOME c' => c' | NONE => error ("No instance parameter for constant " ^ quote c ^ " on type " ^ quote tyco)); fun add_inst_param (c, tyco) inst = (map_inst_params o apfst o Symtab.map_default (c, Symtab.empty)) (Symtab.update_new (tyco, inst)) #> (map_inst_params o apsnd) (Symtab.update_new (#1 inst, (c, tyco))); val inst_of_param = Symtab.lookup o #2 o inst_params_of; val param_of_inst = #1 oo get_inst_param; fun inst_thms thy = Symtab.fold (Symtab.fold (cons o #2 o #2) o #2) (#1 (inst_params_of thy)) []; fun get_inst_tyco consts = try (#1 o dest_Type o the_single o Consts.typargs consts); fun unoverload thy = MetaSimplifier.simplify true (inst_thms thy); fun overload thy = MetaSimplifier.simplify true (map Thm.symmetric (inst_thms thy)); fun unoverload_conv thy = MetaSimplifier.rewrite true (inst_thms thy); fun overload_conv thy = MetaSimplifier.rewrite true (map Thm.symmetric (inst_thms thy)); fun lookup_inst_param consts params (c, T) = (case get_inst_tyco consts (c, T) of SOME tyco => AList.lookup (op =) params (c, tyco) | NONE => NONE); fun unoverload_const thy (c_ty as (c, _)) = if is_some (class_of_param thy c) then (case get_inst_tyco (Sign.consts_of thy) c_ty of SOME tyco => try (param_of_inst thy) (c, tyco) |> the_default c | NONE => c) else c; (** instances **) (* class relations *) fun cert_classrel thy raw_rel = let val string_of_sort = Syntax.string_of_sort_global thy; val (c1, c2) = pairself (Sign.certify_class thy) raw_rel; val _ = Sign.primitive_classrel (c1, c2) (Theory.copy thy); val _ = (case subtract (op =) (all_params_of thy [c1]) (all_params_of thy [c2]) of [] => () | xs => raise TYPE ("Class " ^ string_of_sort [c1] ^ " lacks parameter(s) " ^ commas_quote xs ^ " of " ^ string_of_sort [c2], [], [])); in (c1, c2) end; fun read_classrel thy raw_rel = cert_classrel thy (pairself (ProofContext.read_class (ProofContext.init thy)) raw_rel) handle TYPE (msg, _, _) => error msg; (* declaration and definition of instances of overloaded constants *) fun inst_tyco_of thy (c, T) = (case get_inst_tyco (Sign.consts_of thy) (c, T) of SOME tyco => tyco | NONE => error ("Illegal type for instantiation of class parameter: " ^ quote (c ^ " :: " ^ Syntax.string_of_typ_global thy T))); fun declare_overloaded (c, T) thy = let val class = (case class_of_param thy c of SOME class => class | NONE => error ("Not a class parameter: " ^ quote c)); val tyco = inst_tyco_of thy (c, T); val name_inst = instance_name (tyco, class) ^ "_inst"; val c' = instance_name (tyco, c); val T' = Type.strip_sorts T; in thy |> Sign.qualified_path true (Binding.name name_inst) |> Sign.declare_const ((Binding.name c', T'), NoSyn) |-> (fn const' as Const (c'', _) => Thm.add_def false true (Binding.name (Thm.def_name c'), Logic.mk_equals (Const (c, T'), const')) #>> apsnd Thm.varifyT_global #-> (fn (_, thm) => add_inst_param (c, tyco) (c'', thm) #> PureThy.add_thm ((Binding.conceal (Binding.name c'), thm), []) #> #2 #> pair (Const (c, T)))) ||> Sign.restore_naming thy end; fun define_overloaded b (c, t) thy = let val T = Term.fastype_of t; val tyco = inst_tyco_of thy (c, T); val (c', eq) = get_inst_param thy (c, tyco); val prop = Logic.mk_equals (Const (c', T), t); val b' = Thm.def_binding_optional (Binding.name (instance_name (tyco, c))) b; in thy |> Thm.add_def false false (b', prop) |>> (fn (_, thm) => Drule.transitive_thm OF [eq, thm]) end; (* primitive rules *) val shyps_topped = forall null o #shyps o Thm.rep_thm; fun add_classrel raw_th thy = let val th = Thm.strip_shyps (Thm.transfer thy raw_th); val prop = Thm.plain_prop_of th; fun err () = raise THM ("add_classrel: malformed class relation", 0, [th]); val rel = Logic.dest_classrel prop handle TERM _ => err (); val (c1, c2) = cert_classrel thy rel handle TYPE _ => err (); val th' = th |> Drule.instantiate' [SOME (ctyp_of thy (TVar ((Name.aT, 0), [c1])))] [] |> Thm.unconstrain_allTs; val _ = shyps_topped th' orelse raise Fail "add_classrel: nontop shyps after unconstrain"; in thy |> Sign.primitive_classrel (c1, c2) |> (#2 oo put_trancl_classrel) ((c1, c2), th') |> perhaps complete_arities end; fun add_arity raw_th thy = let val th = Thm.strip_shyps (Thm.transfer thy raw_th); val prop = Thm.plain_prop_of th; fun err () = raise THM ("add_arity: malformed type arity", 0, [th]); val (t, Ss, c) = Logic.dest_arity prop handle TERM _ => err (); val args = Name.names Name.context Name.aT Ss; val T = Type (t, map TFree args); val std_vars = map (fn (a, S) => SOME (ctyp_of thy (TVar ((a, 0), S)))) args; val missing_params = Sign.complete_sort thy [c] |> maps (these o Option.map #params o try (get_info thy)) |> filter_out (fn (const, _) => can (get_inst_param thy) (const, t)) |> (map o apsnd o map_atyps) (K T); val _ = map (Sign.certify_sort thy) Ss = Ss orelse err (); val th' = th |> Drule.instantiate' std_vars [] |> Thm.unconstrain_allTs; val _ = shyps_topped th' orelse raise Fail "add_arity: nontop shyps after unconstrain"; in thy |> fold (#2 oo declare_overloaded) missing_params |> Sign.primitive_arity (t, Ss, [c]) |> put_arity ((t, Ss, c), th') end; (* tactical proofs *) fun prove_classrel raw_rel tac thy = let val ctxt = ProofContext.init thy; val (c1, c2) = cert_classrel thy raw_rel; val th = Goal.prove ctxt [] [] (Logic.mk_classrel (c1, c2)) (K tac) handle ERROR msg => cat_error msg ("The error(s) above occurred while trying to prove class relation " ^ quote (Syntax.string_of_classrel ctxt [c1, c2])); in thy |> PureThy.add_thms [((Binding.name (prefix classrel_prefix (Logic.name_classrel (c1, c2))), th), [])] |-> (fn [th'] => add_classrel th') end; fun prove_arity raw_arity tac thy = let val ctxt = ProofContext.init thy; val arity = ProofContext.cert_arity ctxt raw_arity; val names = map (prefix arity_prefix) (Logic.name_arities arity); val props = Logic.mk_arities arity; val ths = Goal.prove_multi ctxt [] [] props (fn _ => Goal.precise_conjunction_tac (length props) 1 THEN tac) handle ERROR msg => cat_error msg ("The error(s) above occurred while trying to prove type arity " ^ quote (Syntax.string_of_arity ctxt arity)); in thy |> PureThy.add_thms (map (rpair []) (map Binding.name names ~~ ths)) |-> fold add_arity end; (** class definitions **) fun split_defined n eq = let val intro = (eq RS Drule.equal_elim_rule2) |> Conjunction.curry_balanced n |> n = 0 ? Thm.eq_assumption 1; val dests = if n = 0 then [] else (eq RS Drule.equal_elim_rule1) |> Balanced_Tree.dest (fn th => (th RS Conjunction.conjunctionD1, th RS Conjunction.conjunctionD2)) n; in (intro, dests) end; fun define_class (bclass, raw_super) raw_params raw_specs thy = let val ctxt = ProofContext.init thy; val pp = Syntax.pp ctxt; (* class *) val bconst = Binding.map_name Logic.const_of_class bclass; val class = Sign.full_name thy bclass; val super = Sign.minimize_sort thy (Sign.certify_sort thy raw_super); fun check_constraint (a, S) = if Sign.subsort thy (super, S) then () else error ("Sort constraint of type variable " ^ setmp_CRITICAL show_sorts true (Pretty.string_of_typ pp) (TFree (a, S)) ^ " needs to be weaker than " ^ Pretty.string_of_sort pp super); (* params *) val params = raw_params |> map (fn p => let val T = Sign.the_const_type thy p; val _ = (case Term.add_tvarsT T [] of [((a, _), S)] => check_constraint (a, S) | _ => error ("Exactly one type variable expected in class parameter " ^ quote p)); val T' = Term.map_type_tvar (fn _ => TFree (Name.aT, [class])) T; in (p, T') end); (* axioms *) fun prep_axiom t = (case Term.add_tfrees t [] of [(a, S)] => check_constraint (a, S) | [] => () | _ => error ("Multiple type variables in class axiom:\n" ^ Pretty.string_of_term pp t); t |> Term.map_types (Term.map_atyps (fn TFree _ => Term.aT [] | U => U)) |> Logic.close_form); val axiomss = map (map (prep_axiom o Sign.cert_prop thy) o snd) raw_specs; val name_atts = map fst raw_specs; (* definition *) val conjs = Logic.mk_of_sort (Term.aT [], super) @ flat axiomss; val class_eq = Logic.mk_equals (Logic.mk_of_class (Term.aT [], class), Logic.mk_conjunction_balanced conjs); val ([def], def_thy) = thy |> Sign.primitive_class (bclass, super) |> PureThy.add_defs false [((Thm.def_binding bconst, class_eq), [])]; val (raw_intro, (raw_classrel, raw_axioms)) = split_defined (length conjs) def ||> chop (length super); (* facts *) val class_triv = Thm.class_triv def_thy class; val ([(_, [intro]), (_, classrel), (_, axioms)], facts_thy) = def_thy |> Sign.qualified_path true bconst |> PureThy.note_thmss "" [((Binding.name "intro", []), [([Drule.export_without_context raw_intro], [])]), ((Binding.name "super", []), [(map Drule.export_without_context raw_classrel, [])]), ((Binding.name "axioms", []), [(map (fn th => Drule.export_without_context (class_triv RS th)) raw_axioms, [])])] ||> Sign.restore_naming def_thy; (* result *) val axclass = make_axclass (def, intro, axioms, params); val result_thy = facts_thy |> fold (#2 oo put_trancl_classrel) (map (pair class) super ~~ classrel) |> Sign.qualified_path false bconst |> PureThy.note_thmss "" (name_atts ~~ map Thm.simple_fact (unflat axiomss axioms)) |> #2 |> Sign.restore_naming facts_thy |> map_axclasses (Symtab.update (class, axclass)) |> map_params (fold (fn (x, _) => add_param pp (x, class)) params); in (class, result_thy) end; (** axiomatizations **) local (*old-style axioms*) fun add_axiom (b, prop) = Thm.add_axiom (b, prop) #-> (fn (_, thm) => PureThy.add_thm ((b, Drule.export_without_context thm), [])); fun axiomatize prep mk name add raw_args thy = let val args = prep thy raw_args; val specs = mk args; val names = name args; in thy |> fold_map add_axiom (map Binding.name names ~~ specs) |-> fold add end; fun ax_classrel prep = axiomatize (map o prep) (map Logic.mk_classrel) (map (prefix classrel_prefix o Logic.name_classrel)) add_classrel; fun ax_arity prep = axiomatize (prep o ProofContext.init) Logic.mk_arities (map (prefix arity_prefix) o Logic.name_arities) add_arity; fun class_const c = (Logic.const_of_class c, Term.itselfT (Term.aT []) --> propT); fun ax_class prep_class prep_classrel (bclass, raw_super) thy = let val class = Sign.full_name thy bclass; val super = map (prep_class thy) raw_super |> Sign.minimize_sort thy; in thy |> Sign.primitive_class (bclass, super) |> ax_classrel prep_classrel (map (fn c => (class, c)) super) |> Theory.add_deps "" (class_const class) (map class_const super) end; in val axiomatize_class = ax_class Sign.certify_class cert_classrel; val axiomatize_class_cmd = ax_class (ProofContext.read_class o ProofContext.init) read_classrel; val axiomatize_classrel = ax_classrel cert_classrel; val axiomatize_classrel_cmd = ax_classrel read_classrel; val axiomatize_arity = ax_arity ProofContext.cert_arity; val axiomatize_arity_cmd = ax_arity ProofContext.read_arity; end; end;