generate a parameterized correspondence relation
authorkuncar
Mon, 26 Nov 2012 14:20:51 +0100
changeset 50227 01d545993e8c
parent 50226 536ab2e82ead
child 50228 cf1a274bbba6
generate a parameterized correspondence relation
src/HOL/Quotient_Examples/Lift_FSet.thy
src/HOL/Tools/Lifting/lifting_info.ML
src/HOL/Tools/Lifting/lifting_setup.ML
src/HOL/Tools/Lifting/lifting_term.ML
--- a/src/HOL/Quotient_Examples/Lift_FSet.thy	Mon Nov 26 14:20:36 2012 +0100
+++ b/src/HOL/Quotient_Examples/Lift_FSet.thy	Mon Nov 26 14:20:51 2012 +0100
@@ -98,27 +98,26 @@
   @{text "list"} and @{text "fset"} types with the same element type.
   To relate nested types like @{text "'a list list"} and
   @{text "'a fset fset"}, we define a parameterized version of the
-  correspondence relation, @{text "cr_fset'"}. *}
+  correspondence relation, @{text "pcr_fset"}. *}
+
+thm pcr_fset_def
 
-definition cr_fset' :: "('a \<Rightarrow> 'b \<Rightarrow> bool) \<Rightarrow> 'a list \<Rightarrow> 'b fset \<Rightarrow> bool"
-  where "cr_fset' R = list_all2 R OO cr_fset"
-
-lemma right_unique_cr_fset' [transfer_rule]:
-  "right_unique A \<Longrightarrow> right_unique (cr_fset' A)"
-  unfolding cr_fset'_def
+lemma right_unique_pcr_fset [transfer_rule]:
+  "right_unique A \<Longrightarrow> right_unique (pcr_fset A)"
+  unfolding pcr_fset_def
   by (intro right_unique_OO right_unique_list_all2 fset.right_unique)
 
-lemma right_total_cr_fset' [transfer_rule]:
-  "right_total A \<Longrightarrow> right_total (cr_fset' A)"
-  unfolding cr_fset'_def
+lemma right_total_pcr_fset [transfer_rule]:
+  "right_total A \<Longrightarrow> right_total (pcr_fset A)"
+  unfolding pcr_fset_def
   by (intro right_total_OO right_total_list_all2 fset.right_total)
 
-lemma bi_total_cr_fset' [transfer_rule]:
-  "bi_total A \<Longrightarrow> bi_total (cr_fset' A)"
-  unfolding cr_fset'_def
+lemma bi_total_pcr_fset [transfer_rule]:
+  "bi_total A \<Longrightarrow> bi_total (pcr_fset A)"
+  unfolding pcr_fset_def
   by (intro bi_total_OO bi_total_list_all2 fset.bi_total)
 
-text {* Transfer rules for @{text "cr_fset'"} can be derived from the
+text {* Transfer rules for @{text "pcr_fset"} can be derived from the
   existing transfer rules for @{text "cr_fset"} together with the
   transfer rules for the polymorphic raw constants. *}
 
@@ -126,16 +125,16 @@
   could potentially be automated. *}
 
 lemma fnil_transfer [transfer_rule]:
-  "(cr_fset' A) [] fnil"
-  unfolding cr_fset'_def
+  "(pcr_fset A) [] fnil"
+  unfolding pcr_fset_def
   apply (rule relcomppI)
   apply (rule Nil_transfer)
   apply (rule fnil.transfer)
   done
 
 lemma fcons_transfer [transfer_rule]:
-  "(A ===> cr_fset' A ===> cr_fset' A) Cons fcons"
-  unfolding cr_fset'_def
+  "(A ===> pcr_fset A ===> pcr_fset A) Cons fcons"
+  unfolding pcr_fset_def
   apply (intro fun_relI)
   apply (elim relcomppE)
   apply (rule relcomppI)
@@ -144,8 +143,8 @@
   done
 
 lemma fappend_transfer [transfer_rule]:
-  "(cr_fset' A ===> cr_fset' A ===> cr_fset' A) append fappend"
-  unfolding cr_fset'_def
+  "(pcr_fset A ===> pcr_fset A ===> pcr_fset A) append fappend"
+  unfolding pcr_fset_def
   apply (intro fun_relI)
   apply (elim relcomppE)
   apply (rule relcomppI)
@@ -154,8 +153,8 @@
   done
 
 lemma fmap_transfer [transfer_rule]:
-  "((A ===> B) ===> cr_fset' A ===> cr_fset' B) map fmap"
-  unfolding cr_fset'_def
+  "((A ===> B) ===> pcr_fset A ===> pcr_fset B) map fmap"
+  unfolding pcr_fset_def
   apply (intro fun_relI)
   apply (elim relcomppE)
   apply (rule relcomppI)
@@ -164,8 +163,8 @@
   done
 
 lemma ffilter_transfer [transfer_rule]:
-  "((A ===> op =) ===> cr_fset' A ===> cr_fset' A) filter ffilter"
-  unfolding cr_fset'_def
+  "((A ===> op =) ===> pcr_fset A ===> pcr_fset A) filter ffilter"
+  unfolding pcr_fset_def
   apply (intro fun_relI)
   apply (elim relcomppE)
   apply (rule relcomppI)
@@ -174,8 +173,8 @@
   done
 
 lemma fset_transfer [transfer_rule]:
-  "(cr_fset' A ===> set_rel A) set fset"
-  unfolding cr_fset'_def
+  "(pcr_fset A ===> set_rel A) set fset"
+  unfolding pcr_fset_def
   apply (intro fun_relI)
   apply (elim relcomppE)
   apply (drule fset.transfer [THEN fun_relD, unfolded relator_eq])
@@ -184,8 +183,8 @@
   done
 
 lemma fconcat_transfer [transfer_rule]:
-  "(cr_fset' (cr_fset' A) ===> cr_fset' A) concat fconcat"
-  unfolding cr_fset'_def
+  "(pcr_fset (pcr_fset A) ===> pcr_fset A) concat fconcat"
+  unfolding pcr_fset_def
   unfolding list_all2_OO
   apply (intro fun_relI)
   apply (elim relcomppE)
@@ -202,8 +201,8 @@
 
 lemma fset_eq_transfer [transfer_rule]:
   assumes "bi_unique A"
-  shows "(cr_fset' A ===> cr_fset' A ===> op =) list_eq (op =)"
-  unfolding cr_fset'_def
+  shows "(pcr_fset A ===> pcr_fset A ===> op =) list_eq (op =)"
+  unfolding pcr_fset_def
   apply (intro fun_relI)
   apply (elim relcomppE)
   apply (rule trans)
--- a/src/HOL/Tools/Lifting/lifting_info.ML	Mon Nov 26 14:20:36 2012 +0100
+++ b/src/HOL/Tools/Lifting/lifting_info.ML	Mon Nov 26 14:20:51 2012 +0100
@@ -11,7 +11,7 @@
   val lookup_quotmaps_global: theory -> string -> quotmaps option
   val print_quotmaps: Proof.context -> unit
 
-  type quotients = {quot_thm: thm}
+  type quotients = {quot_thm: thm, pcrel_def: thm option}
   val transform_quotients: morphism -> quotients -> quotients
   val lookup_quotients: Proof.context -> string -> quotients option
   val lookup_quotients_global: theory -> string -> quotients option
@@ -118,7 +118,7 @@
   end
 
 (* info about quotient types *)
-type quotients = {quot_thm: thm}
+type quotients = {quot_thm: thm, pcrel_def: thm option}
 
 structure Quotients = Generic_Data
 (
@@ -128,8 +128,8 @@
   fun merge data = Symtab.merge (K true) data
 )
 
-fun transform_quotients phi {quot_thm} =
-  {quot_thm = Morphism.thm phi quot_thm}
+fun transform_quotients phi {quot_thm, pcrel_def} =
+  {quot_thm = Morphism.thm phi quot_thm, pcrel_def = Option.map (Morphism.thm phi) pcrel_def}
 
 val lookup_quotients = Symtab.lookup o Quotients.get o Context.Proof
 val lookup_quotients_global = Symtab.lookup o Quotients.get o Context.Theory
@@ -144,8 +144,8 @@
     val maybe_stored_quot_thm = Symtab.lookup symtab qty_full_name
   in
     case maybe_stored_quot_thm of
-      SOME {quot_thm = stored_quot_thm} => 
-        if Thm.eq_thm_prop (stored_quot_thm, quot_thm) then
+      SOME data => 
+        if Thm.eq_thm_prop (#quot_thm data, quot_thm) then
           Quotients.map (Symtab.delete qty_full_name) ctxt
         else
           ctxt
@@ -157,12 +157,14 @@
 
 fun print_quotients ctxt =
   let
-    fun prt_quot (qty_name, {quot_thm}) =
+    fun prt_quot (qty_name, {quot_thm, pcrel_def}) =
       Pretty.block (separate (Pretty.brk 2)
        [Pretty.str "type:", 
         Pretty.str qty_name,
         Pretty.str "quot. thm:",
-        Syntax.pretty_term ctxt (prop_of quot_thm)])
+        Syntax.pretty_term ctxt (prop_of quot_thm),
+        Pretty.str "pcrel_def thm:",
+        option_fold (Pretty.str "-") ((Syntax.pretty_term ctxt) o prop_of) pcrel_def])
   in
     map prt_quot (Symtab.dest (Quotients.get (Context.Proof ctxt)))
     |> Pretty.big_list "quotients:"
--- a/src/HOL/Tools/Lifting/lifting_setup.ML	Mon Nov 26 14:20:36 2012 +0100
+++ b/src/HOL/Tools/Lifting/lifting_setup.ML	Mon Nov 26 14:20:51 2012 +0100
@@ -22,20 +22,62 @@
 
 exception SETUP_LIFTING_INFR of string
 
-fun define_cr_rel rep_fun lthy =
+fun define_crel rep_fun lthy =
   let
     val (qty, rty) = (dest_funT o fastype_of) rep_fun
     val rep_fun_graph = (HOLogic.eq_const rty) $ Bound 1 $ (rep_fun $ Bound 0)
     val def_term = Abs ("x", rty, Abs ("y", qty, rep_fun_graph));
     val qty_name = (Binding.name o Long_Name.base_name o fst o dest_Type) qty
-    val cr_rel_name = Binding.prefix_name "cr_" qty_name
+    val crel_name = Binding.prefix_name "cr_" qty_name
     val (fixed_def_term, lthy') = yield_singleton (Variable.importT_terms) def_term lthy
     val ((_, (_ , def_thm)), lthy'') =
-      Local_Theory.define ((cr_rel_name, NoSyn), ((Thm.def_binding cr_rel_name, []), fixed_def_term)) lthy'
+      Local_Theory.define ((crel_name, NoSyn), ((Thm.def_binding crel_name, []), fixed_def_term)) lthy'
   in
     (def_thm, lthy'')
   end
 
+fun print_define_pcrel_warning msg = 
+  let
+    val warning_msg = cat_lines 
+      ["Generation of a parametrized correspondence relation failed.",
+      (Pretty.string_of (Pretty.block
+         [Pretty.str "Reason:", Pretty.brk 2, msg]))]
+  in
+    warning warning_msg
+  end
+
+fun define_pcrel crel lthy =
+  let
+    val pcrel = Morphism.term (Local_Theory.target_morphism lthy) crel
+    val [crel_poly] = Variable.polymorphic lthy [pcrel]
+    val rty_raw = (domain_type o fastype_of) crel_poly
+    val (quot_thm, assms) = Lifting_Term.prove_param_quot_thm lthy rty_raw
+    val args = map (fn (_, q_thm) => quot_thm_crel q_thm) assms
+    val parametrized_relator = quot_thm_crel quot_thm
+    val [rty, rty'] = (binder_types o fastype_of) parametrized_relator
+    val thy = Proof_Context.theory_of lthy
+    val tyenv_match = Sign.typ_match thy (rty_raw, rty') Vartab.empty
+    val crel_subst = Envir.subst_term (tyenv_match,Vartab.empty) crel_poly
+    val lthy = Variable.declare_names parametrized_relator lthy
+    val (crel_typed, lthy) = yield_singleton Variable.importT_terms crel_subst lthy
+    val qty = (domain_type o range_type o fastype_of) crel_typed
+    val relcomp_op = Const (@{const_name "relcompp"}, 
+          (rty --> rty' --> HOLogic.boolT) --> 
+          (rty' --> qty --> HOLogic.boolT) --> 
+          rty --> qty --> HOLogic.boolT)
+    val relator_type = foldr1 (op -->) ((map type_of args) @ [rty, qty, HOLogic.boolT])
+    val qty_name = (fst o dest_Type) qty
+    val pcrel_name = Binding.prefix_name "pcr_" ((Binding.name o Long_Name.base_name) qty_name)
+    val lhs = Library.foldl (op $) ((Free (Binding.name_of pcrel_name, relator_type)), args)
+    val rhs = relcomp_op $ parametrized_relator $ crel_typed
+    val definition_term = Logic.mk_equals (lhs, rhs)
+    val ((_, (_, def_thm)), lthy) = Specification.definition ((SOME (pcrel_name, SOME relator_type, NoSyn)), 
+      ((Binding.empty, []), definition_term)) lthy
+  in
+    (SOME def_thm, lthy)
+  end
+  handle Lifting_Term.PARAM_QUOT_THM (_, msg) => (print_define_pcrel_warning msg; (NONE, lthy))
+
 fun define_code_constr gen_code quot_thm lthy =
   let
     val abs = quot_thm_abs quot_thm
@@ -95,10 +137,11 @@
   let
     val _ = quot_thm_sanity_check lthy quot_thm
     val (_, qtyp) = quot_thm_rty_qty quot_thm
-    val qty_full_name = (fst o dest_Type) qtyp
-    val quotients = { quot_thm = quot_thm }
+    val (pcrel_def, lthy) = define_pcrel (quot_thm_crel quot_thm) lthy
+    val quotients = { quot_thm = quot_thm, pcrel_def = pcrel_def }
+    val qty_full_name = (fst o dest_Type) qtyp  
     fun quot_info phi = Lifting_Info.transform_quotients phi quotients
-    val lthy' = case maybe_reflp_thm of
+    val lthy = case maybe_reflp_thm of
       SOME reflp_thm => lthy
         |> (snd oo Local_Theory.note) ((Binding.empty, [Lifting_Info.add_reflexivity_rule_attrib]),
               [reflp_thm])
@@ -108,7 +151,7 @@
       | NONE => lthy
         |> define_abs_type gen_code quot_thm
   in
-    lthy'
+    lthy
       |> Local_Theory.declaration {syntax = false, pervasive = true}
         (fn phi => Lifting_Info.update_quotients qty_full_name (quot_info phi))
   end
@@ -130,7 +173,7 @@
     val induct_attr = Attrib.internal (K (Induct.induct_type (fst (dest_Type qty))))
     val qty_name = (Binding.name o Long_Name.base_name o fst o dest_Type) qty
     fun qualify suffix = Binding.qualified true suffix qty_name
-    val lthy' = case maybe_reflp_thm of
+    val lthy = case maybe_reflp_thm of
       SOME reflp_thm => lthy
         |> (snd oo Local_Theory.note) ((qualify "bi_total", [transfer_attr]), 
           [[quot_thm, reflp_thm] MRSL @{thm Quotient_bi_total}])
@@ -150,7 +193,7 @@
         |> (snd oo Local_Theory.note) ((qualify "abs_induct", [induct_attr]),
           [quot_thm RS @{thm Quotient_abs_induct}])
   in
-    lthy'
+    lthy
       |> (snd oo Local_Theory.note) ((qualify "right_unique", [transfer_attr]), 
         [quot_thm RS @{thm Quotient_right_unique}])
       |> (snd oo Local_Theory.note) ((qualify "right_total", [transfer_attr]), 
@@ -172,7 +215,7 @@
   let
     val transfer_attr = Attrib.internal (K Transfer.transfer_add)
     val (_ $ rep_fun $ _ $ typedef_set) = (HOLogic.dest_Trueprop o prop_of) typedef_thm
-    val (T_def, lthy') = define_cr_rel rep_fun lthy
+    val (T_def, lthy') = define_crel rep_fun lthy
 
     val quot_thm = case typedef_set of
       Const ("Orderings.top_class.top", _) => 
--- a/src/HOL/Tools/Lifting/lifting_term.ML	Mon Nov 26 14:20:36 2012 +0100
+++ b/src/HOL/Tools/Lifting/lifting_term.ML	Mon Nov 26 14:20:51 2012 +0100
@@ -7,6 +7,7 @@
 signature LIFTING_TERM =
 sig
   exception QUOT_THM of typ * typ * Pretty.T
+  exception PARAM_QUOT_THM of typ * Pretty.T
   exception CHECK_RTY of typ * typ
 
   val prove_quot_thm: Proof.context -> typ * typ -> thm
@@ -14,17 +15,19 @@
   val abs_fun: Proof.context -> typ * typ -> term
 
   val equiv_relation: Proof.context -> typ * typ -> term
+
+  val prove_param_quot_thm: Proof.context -> typ -> thm * (typ * thm) list
 end
 
 structure Lifting_Term: LIFTING_TERM =
 struct
-
 open Lifting_Util
 
 infix 0 MRSL
 
 exception QUOT_THM_INTERNAL of Pretty.T
 exception QUOT_THM of typ * typ * Pretty.T
+exception PARAM_QUOT_THM of typ * Pretty.T
 exception CHECK_RTY of typ * typ
 
 fun match ctxt err ty_pat ty =
@@ -235,4 +238,51 @@
 fun equiv_relation ctxt (rty, qty) =
   quot_thm_rel (prove_quot_thm ctxt (rty, qty))
 
+fun get_fresh_Q_t ctxt =
+  let
+    val Q_t = Syntax.read_term ctxt "Trueprop (Quotient R Abs Rep T)"
+    val ctxt = Variable.declare_names Q_t ctxt
+    val frees_Q_t = Term.add_free_names Q_t []
+    val (_, ctxt) = Variable.variant_fixes frees_Q_t ctxt
+  in
+    (Q_t, ctxt)
+  end
+
+fun prove_param_quot_thm ctxt ty = 
+  let 
+    fun generate (ty as Type (s, tys)) (table_ctxt as (table, ctxt)) =
+      if null tys 
+      then 
+        let 
+          val thy = Proof_Context.theory_of ctxt
+          val instantiated_id_quot_thm = instantiate' [SOME (ctyp_of thy ty)] [] @{thm identity_quotient}
+        in
+          (instantiated_id_quot_thm, (table, ctxt)) 
+        end
+      else
+        let
+          val (args, table_ctxt) = fold_map generate tys table_ctxt
+        in
+          (args MRSL (get_rel_quot_thm ctxt s), table_ctxt)
+        end 
+      | generate (ty as (TVar _)) (table, ctxt) =
+        if AList.defined (op=) table ty 
+        then (the (AList.lookup (op=) table ty), (table, ctxt))
+        else 
+          let
+            val thy = Proof_Context.theory_of ctxt
+            val (Q_t, ctxt') = get_fresh_Q_t ctxt
+            val Q_thm = Thm.assume (cterm_of thy Q_t)
+            val table' = (ty, Q_thm)::table
+          in
+            (Q_thm, (table', ctxt'))
+          end
+      | generate _ _ = error "generate_param_quot_thm: TFree"
+
+    val (param_quot_thm, (table, _)) = generate ty ([], ctxt)
+  in
+    (param_quot_thm, rev table)
+  end
+  handle QUOT_THM_INTERNAL pretty_msg => raise PARAM_QUOT_THM (ty, pretty_msg)
+
 end;