(added to repository)
authorhaftmann
Tue, 09 Aug 2005 08:56:34 +0200
changeset 17036 9b57e5aa4c93
parent 17035 415e897405da
child 17037 bd15f69bd947
(added to repository)
src/Pure/hugsclass.ML
--- a/src/Pure/hugsclass.ML	Tue Aug 09 08:54:41 2005 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,359 +0,0 @@
-(*  Title:      Pure/hugsclass.ML
-    ID:         $Id$
-    Author:     Florian Haftmann, TU Muenchen
-
-Haskell98-like type classes, logically simulated by locales ("hugsclass")
-*)
-
-(*!!! for now, only experimental scratch code !!!*)
-
-signature HUGSCLASS =
-sig
-  val add_hugsclass: bstring -> xstring list -> Locale.element list -> theory -> theory
-(*   val add_hugsclass_i: bstring -> string list -> Locale.element list -> theory -> theory  *)
-
-  val get_locale_for_hugsclass: theory -> string -> string
-  val get_axclass_for_hugsclass: theory -> string -> class
-  val add_members_x: xstring * xstring list -> theory -> theory
-  val add_members: string * string list -> theory -> theory
-  val add_tycons_x: xstring * xstring list -> theory -> theory
-  val add_tycons: string * string list -> theory -> theory
-  val the_members: theory -> class -> string list
-  val the_tycons: theory -> class -> string list
-
-  val is_hugsclass: theory -> class -> bool
-  val get_arities: theory -> sort -> string -> sort list
-  val get_superclasses: theory -> class -> class list
-end;
-
-structure Hugsclass : HUGSCLASS =
-struct
-
-
-
-(** data kind 'Pure/classes' **)
-
-type hugsclass_info = {
-  locale_name: string,
-  axclass_name: string,
-  members: string list,
-  tycons: string list
-};
-
-structure HugsclassesData = TheoryDataFun (
-  struct
-    val name = "Pure/hugsclasses";
-    type T = hugsclass_info Symtab.table;
-    val empty = Symtab.empty;
-    val copy = I;
-    val extend = I;
-    fun merge _ = Symtab.merge (K true);
-    fun print _ tab = (Pretty.writeln o Pretty.chunks) (map Pretty.str (Symtab.keys tab));
-  end
-);
-
-val _ = Context.add_setup [HugsclassesData.init];
-val print_hugsclasses = HugsclassesData.print;
-
-fun lookup_hugsclass_info thy class = Symtab.lookup (HugsclassesData.get thy, class);
-
-fun get_hugsclass_info thy class =
-  case lookup_hugsclass_info thy class
-    of NONE => error ("undeclared hugs class " ^ quote class)
-     | SOME info => info;
-
-fun put_hugsclass_info class info thy =
-  thy
-  |> HugsclassesData.put (Symtab.update ((class, info), HugsclassesData.get thy));
-
-
-(* name mangling *)
-
-fun get_locale_for_hugsclass thy class =
-  #locale_name (get_hugsclass_info thy class)
-
-fun get_axclass_for_hugsclass thy class =
-  #axclass_name (get_hugsclass_info thy class)
-
-
-(* assign members to type classes *)
-
-local
-
-fun gen_add_members prep_class prep_member (raw_class, raw_members_new) thy =
-  let
-    val class = prep_class thy raw_class
-    val members_new = map (prep_member thy) raw_members_new
-    val {locale_name, axclass_name, members, tycons} =
-      get_hugsclass_info thy class
-  in
-    thy
-    |> put_hugsclass_info class {
-         locale_name = locale_name,
-         axclass_name = axclass_name,
-         members = members @ members_new,
-         tycons = tycons
-       }
-  end
-
-in
-
-val add_members_x = gen_add_members Sign.intern_class Sign.intern_const
-val add_members = gen_add_members (K I) (K I)
-
-end
-
-
-(* assign type constructors to type classes *)
-
-local
-
-fun gen_add_tycons prep_class prep_type (raw_class, raw_tycons_new) thy =
-  let
-    val class = prep_class thy raw_class
-    val tycons_new = map (prep_type thy) raw_tycons_new
-    val {locale_name, axclass_name, members, tycons} =
-      get_hugsclass_info thy class
-  in
-    thy
-    |> put_hugsclass_info class {
-         locale_name = locale_name,
-         axclass_name = axclass_name,
-         members = members,
-         tycons = tycons @ tycons_new
-       }
-  end;
-
-in
-
-val add_tycons_x = gen_add_tycons Sign.intern_class Sign.intern_type
-val add_tycons = gen_add_tycons (K I) (K I)
-
-end
-
-
-(* retrieve members *)
-
-val the_members = (#members oo get_hugsclass_info)
-
-
-(* retrieve type constructor associations *)
-
-val the_tycons = (#tycons oo get_hugsclass_info)
-
-
-
-(** class declaration **)
-
-local
-
-fun gen_add_hugsclass prep_class bname raw_superclss raw_locelems thy =
-  let
-    val name_class = Sign.full_name thy bname
-    val name_loc = Sign.full_name thy bname
-    val superclss = map (prep_class thy) raw_superclss
-    val _ = map (get_hugsclass_info thy) superclss
-    val defaultS = Sign.defaultS thy
-    val axsuperclss = case superclss of [] => defaultS
-                                     | _ => superclss
-    val locexpr =
-      superclss
-      |> map (get_locale_for_hugsclass thy) 
-      |> map (Locale.Locale)
-      |> Locale.Merge
-    (* fun inferT_axm pre_tm =
-      let
-        val pp = Sign.pp thy;
-        val (t, _) = Sign.infer_types pp thy (K NONE) (K NONE) [] true ([pre_tm], TFree ("a", []));
-      in t end
-    fun axiom_for members = (bname, inferT_axm
-      (ObjectLogic.assert_propT thy (list_comb (Const (name, dummyT), map (fn (mname, mtyp, _) => Const (mname, mtyp)) members)))) *)
-    fun constify thy (mname, mtyp, _) = Const (Sign.intern_const thy mname, mtyp)
-    fun axiom_for loc members thy = case Sign.const_type thy loc
-      of SOME pred_type => [((bname, 
-         (ObjectLogic.assert_propT thy
-           (list_comb (Const (loc, Type.unvarifyT pred_type), map (constify thy) members)))), [])
-        ]
-       | NONE => (writeln "--- no const_type"; [])
-    fun get_members locname thy =
-      let
-        val ctxt = ProofContext.init thy
-                   |> Locale.read_context_statement (SOME locname) [] []
-                   |> #4
-                   |> `(fn ctxt => ((writeln o commas o ProofContext.fixed_names_of) ctxt; ctxt)) |> snd
-        val ctx' = ProofContext.init thy
-                   |> Locale.read_context_statement (SOME locname) [] []
-                   |> #3
-                   |> `(fn ctxt => ((writeln o commas o ProofContext.fixed_names_of) ctxt; ctxt)) |> snd
-        val fixed = ProofContext.fixed_names_of ctxt
-        fun mk_member fixed = (fixed, (the o ProofContext.default_type ctxt) fixed, NoSyn)
-      in map mk_member fixed end;
-    fun add_constraint class (mname, mtyp, _) thy =
-      let
-        val classes = snd (#classes (Type.rep_tsig (#tsig (Sign.rep_sg thy))))
-        val tfree = case (typ_tfrees o Type.unvarifyT) mtyp
-                    of [(tfree, sort)] => if Sorts.sort_eq classes (sort, defaultS)
-                                          then tfree
-                                          else error ("sort constraint not permitted in member " ^ quote mname)
-                     | _ => error ("no or more than one type variable in declaration for member " ^ quote mname)
-        fun constrain_tfree (tfree, _) = TFree (tfree, [class])
-      in Sign.add_const_constraint_i
-        (Sign.intern_const thy mname, map_type_tfree constrain_tfree mtyp) thy
-      end;
-  in
-    thy
-    |> Locale.add_locale true bname locexpr raw_locelems
-    |> `(fn _ => writeln "(1) added locale") |> snd
-    |> `(get_members name_loc)
-       |-> (fn members =>
-       Sign.add_consts_i members
-    #> `(fn _ => writeln "(2) added members") #> snd
-    #> `(axiom_for name_loc members)
-       #-> (fn axiom =>
-       AxClass.add_axclass_i (bname, axsuperclss) axiom #> fst
-    #> `(fn _ => writeln "(3) added axclass") #> snd
-    #> fold (add_constraint name_class) members
-    #> `(fn _ => writeln "(4) constrained members") #> snd
-    #> add_members (name_class, map #1 members)
-    #> `(fn _ => writeln "(5) added class members") #> snd
-    #> put_hugsclass_info name_class {
-         locale_name = name_loc,
-         axclass_name = name_class,
-         members = [],
-         tycons = []
-       }
-    ))
-  end
-
-in
-
-val add_hugsclass = gen_add_hugsclass (Sign.intern_class);
-val add_hugsclass_i = gen_add_hugsclass (K I);
-
-end;
-
-
-
-(** technical class relations *)
-
-fun is_hugsclass thy = can (the_tycons thy)
-
-fun get_arities thy sort tycons =
-  let
-    val tsig = Type.rep_tsig (#tsig (Sign.rep_sg thy))
-    val clss_arities = (snd (#classes tsig), #arities tsig)
-  in
-    Sorts.mg_domain clss_arities tycons sort
-    |> map (filter (is_hugsclass thy))
-    (*!!! assert -> error on fail *)
-  end
-
-fun get_superclasses thy class =
-  Sorts.direct_supercls (snd (#classes (Type.rep_tsig (#tsig (Sign.rep_sg thy))))) class
-  |> filter (is_hugsclass thy)
-
-
-(** outer syntax **)
-
-local
-
-structure P = OuterParse
-and K = OuterSyntax.Keyword
-
-in
-
-val (classK, extendsK) = ("class", "extends")
-
-val classP =
-  OuterSyntax.command classK "define type class" K.thy_decl (
-    P.name
-    -- Scan.optional (P.$$$ extendsK |-- P.list1 P.xname) []
-    -- Scan.repeat P.locale_element
-    >> (fn (((name, superclss), locelems))
-        => Toplevel.theory (add_hugsclass name superclss locelems))
-  )
-
-val (instanceK, whereK) = ("inst", "where")
-
-val instanceP =
-  OuterSyntax.command instanceK "prove type arity" K.thy_goal ((
-    Scan.optional (P.$$$ "(" |-- P.!!! (P.list1 (P.group "sort" P.xname) --| P.$$$ ")")) []
-    -- P.xname --| P.$$$ "::"
-    -- P.group "class" P.xname
-    -- Scan.optional (P.$$$ whereK |-- Scan.repeat1 P.spec_name) [])
-    >> (fn (((arity, ty), class), defs)
-        =>
-        Toplevel.theory (IsarThy.add_defs (true, defs))
-        #> (AxClass.instance_arity_proof (ty, arity, class)
-            |> (Toplevel.print oo Toplevel.theory_to_proof))
-       )
-  )
-
-val _ = OuterSyntax.add_parsers [classP, instanceP]
-
-val _ = OuterSyntax.add_keywords [extendsK]
-
-end
-
-end
-
-(*
-
-PureThy.add_thms [Thm.no_attributes (intro_name bclass, intro)]
-get_thm thy PureThy.
-
-rename intro rule
-check defs -> should contain any member
-wie syntax extrahieren?
-cases für locales
-
-isomorphism
-
-locale sg = fixes prod assumes assoc: ...
-
-consts prod :: "'a::type => 'a => 'a"
-
-axclass sg < type
-  sg: "sg prod"
-
-constraints prod :: "'a::sg => 'a => 'a"
-
-
-theory Scratch imports Main begin
-
-(* class definition *)
-
-locale sg =
-  fixes f :: "'a \<Rightarrow> 'a \<Rightarrow> 'a" (infix "\<degree>" 60)
-  assumes assoc: "(x \<degree> y) \<degree> z = x \<degree> (y \<degree> z)"
-
-classes sg
-consts prod :: "'a::sg \<Rightarrow> 'a \<Rightarrow> 'a"  (infix "\<degree>\<degree>" 60)
-classrel sg < type
-axioms sg: "sg prod"
-
-interpretation sg: sg [prod] by (rule sg)
-
-
-(* abstract reasoning *)
-
-lemma (in sg)
-  bar: "x \<degree> y = x \<degree> y" ..
-
-lemma baz:
-  fixes x :: "'a::sg"
-  shows "x \<degree>\<degree> y = x \<degree>\<degree> y" ..
-
-(* class instantiation *)
-
-interpretation sg_list: sg ["op @"]
-  by (rule sg.intro) (simp only: append_assoc)
-arities list :: (type) sg
-defs (overloaded) prod_list_def: "prod == op @"
-
-interpretation sg_prod: sg ["%p q. (fst p \<degree>\<degree> fst q, snd p \<degree>\<degree> snd q)"]
-  by (rule sg.intro) (simp add: sg.assoc)
-
-arities * :: (sg, sg) sg
-
-*)