--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/Attic/Quot/quotient_tacs.ML Thu Feb 25 07:57:17 2010 +0100
@@ -0,0 +1,665 @@
+(* Title: quotient_tacs.thy
+ Author: Cezary Kaliszyk and Christian Urban
+
+ Tactics for solving goal arising from lifting
+ theorems to quotient types.
+*)
+
+signature QUOTIENT_TACS =
+sig
+ val regularize_tac: Proof.context -> int -> tactic
+ val injection_tac: Proof.context -> int -> tactic
+ val all_injection_tac: Proof.context -> int -> tactic
+ val clean_tac: Proof.context -> int -> tactic
+ val procedure_tac: Proof.context -> thm -> int -> tactic
+ val lift_tac: Proof.context -> thm list -> int -> tactic
+ val quotient_tac: Proof.context -> int -> tactic
+ val quot_true_tac: Proof.context -> (term -> term) -> int -> tactic
+ val lifted_attrib: attribute
+end;
+
+structure Quotient_Tacs: QUOTIENT_TACS =
+struct
+
+open Quotient_Info;
+open Quotient_Term;
+
+
+(** various helper fuctions **)
+
+(* Since HOL_basic_ss is too "big" for us, we *)
+(* need to set up our own minimal simpset. *)
+fun mk_minimal_ss ctxt =
+ Simplifier.context ctxt empty_ss
+ setsubgoaler asm_simp_tac
+ setmksimps (mksimps [])
+
+(* composition of two theorems, used in maps *)
+fun OF1 thm1 thm2 = thm2 RS thm1
+
+(* prints a warning, if the subgoal is not solved *)
+fun WARN (tac, msg) i st =
+ case Seq.pull (SOLVED' tac i st) of
+ NONE => (warning msg; Seq.single st)
+ | seqcell => Seq.make (fn () => seqcell)
+
+fun RANGE_WARN tacs = RANGE (map WARN tacs)
+
+fun atomize_thm thm =
+let
+ val thm' = Thm.freezeT (forall_intr_vars thm) (* FIXME/TODO: is this proper Isar-technology? *)
+ val thm'' = ObjectLogic.atomize (cprop_of thm')
+in
+ @{thm equal_elim_rule1} OF [thm'', thm']
+end
+
+
+
+(*** Regularize Tactic ***)
+
+(** solvers for equivp and quotient assumptions **)
+
+fun equiv_tac ctxt =
+ REPEAT_ALL_NEW (resolve_tac (equiv_rules_get ctxt))
+
+fun equiv_solver_tac ss = equiv_tac (Simplifier.the_context ss)
+val equiv_solver = Simplifier.mk_solver' "Equivalence goal solver" equiv_solver_tac
+
+fun quotient_tac ctxt =
+ (REPEAT_ALL_NEW (FIRST'
+ [rtac @{thm identity_quotient},
+ resolve_tac (quotient_rules_get ctxt)]))
+
+fun quotient_solver_tac ss = quotient_tac (Simplifier.the_context ss)
+val quotient_solver =
+ Simplifier.mk_solver' "Quotient goal solver" quotient_solver_tac
+
+fun solve_quotient_assm ctxt thm =
+ case Seq.pull (quotient_tac ctxt 1 thm) of
+ SOME (t, _) => t
+ | _ => error "Solve_quotient_assm failed. Possibly a quotient theorem is missing."
+
+
+fun prep_trm thy (x, (T, t)) =
+ (cterm_of thy (Var (x, T)), cterm_of thy t)
+
+fun prep_ty thy (x, (S, ty)) =
+ (ctyp_of thy (TVar (x, S)), ctyp_of thy ty)
+
+fun get_match_inst thy pat trm =
+let
+ val univ = Unify.matchers thy [(pat, trm)]
+ val SOME (env, _) = Seq.pull univ (* raises BIND, if no unifier *)
+ val tenv = Vartab.dest (Envir.term_env env)
+ val tyenv = Vartab.dest (Envir.type_env env)
+in
+ (map (prep_ty thy) tyenv, map (prep_trm thy) tenv)
+end
+
+(* Calculates the instantiations for the lemmas:
+
+ ball_reg_eqv_range and bex_reg_eqv_range
+
+ Since the left-hand-side contains a non-pattern '?P (f ?x)'
+ we rely on unification/instantiation to check whether the
+ theorem applies and return NONE if it doesn't.
+*)
+fun calculate_inst ctxt ball_bex_thm redex R1 R2 =
+let
+ val thy = ProofContext.theory_of ctxt
+ fun get_lhs thm = fst (Logic.dest_equals (Thm.concl_of thm))
+ val ty_inst = map (SOME o ctyp_of thy) [domain_type (fastype_of R2)]
+ val trm_inst = map (SOME o cterm_of thy) [R2, R1]
+in
+ case try (Drule.instantiate' ty_inst trm_inst) ball_bex_thm of
+ NONE => NONE
+ | SOME thm' =>
+ (case try (get_match_inst thy (get_lhs thm')) redex of
+ NONE => NONE
+ | SOME inst2 => try (Drule.instantiate inst2) thm')
+end
+
+fun ball_bex_range_simproc ss redex =
+let
+ val ctxt = Simplifier.the_context ss
+in
+ case redex of
+ (Const (@{const_name "Ball"}, _) $ (Const (@{const_name "Respects"}, _) $
+ (Const (@{const_name "fun_rel"}, _) $ R1 $ R2)) $ _) =>
+ calculate_inst ctxt @{thm ball_reg_eqv_range[THEN eq_reflection]} redex R1 R2
+
+ | (Const (@{const_name "Bex"}, _) $ (Const (@{const_name "Respects"}, _) $
+ (Const (@{const_name "fun_rel"}, _) $ R1 $ R2)) $ _) =>
+ calculate_inst ctxt @{thm bex_reg_eqv_range[THEN eq_reflection]} redex R1 R2
+
+ | _ => NONE
+end
+
+(* Regularize works as follows:
+
+ 0. preliminary simplification step according to
+ ball_reg_eqv bex_reg_eqv babs_reg_eqv ball_reg_eqv_range bex_reg_eqv_range
+
+ 1. eliminating simple Ball/Bex instances (ball_reg_right bex_reg_left)
+
+ 2. monos
+
+ 3. commutation rules for ball and bex (ball_all_comm bex_ex_comm)
+
+ 4. then rel-equalities, which need to be instantiated with 'eq_imp_rel'
+ to avoid loops
+
+ 5. then simplification like 0
+
+ finally jump back to 1
+*)
+
+fun regularize_tac ctxt =
+let
+ val thy = ProofContext.theory_of ctxt
+ val ball_pat = @{term "Ball (Respects (R1 ===> R2)) P"}
+ val bex_pat = @{term "Bex (Respects (R1 ===> R2)) P"}
+ val simproc = Simplifier.simproc_i thy "" [ball_pat, bex_pat] (K (ball_bex_range_simproc))
+ val simpset = (mk_minimal_ss ctxt)
+ addsimps @{thms ball_reg_eqv bex_reg_eqv babs_reg_eqv babs_simp}
+ addsimprocs [simproc]
+ addSolver equiv_solver addSolver quotient_solver
+ val eq_imp_rel = @{lemma "equivp R ==> a = b --> R a b" by (simp add: equivp_reflp)}
+ val eq_eqvs = map (OF1 eq_imp_rel) (equiv_rules_get ctxt)
+in
+ simp_tac simpset THEN'
+ REPEAT_ALL_NEW (CHANGED o FIRST'
+ [resolve_tac @{thms ball_reg_right bex_reg_left bex1_bexeq_reg},
+ resolve_tac (Inductive.get_monos ctxt),
+ resolve_tac @{thms ball_all_comm bex_ex_comm},
+ resolve_tac eq_eqvs,
+ simp_tac simpset])
+end
+
+
+
+(*** Injection Tactic ***)
+
+(* Looks for Quot_True assumptions, and in case its parameter
+ is an application, it returns the function and the argument.
+*)
+fun find_qt_asm asms =
+let
+ fun find_fun trm =
+ case trm of
+ (Const(@{const_name Trueprop}, _) $ (Const (@{const_name Quot_True}, _) $ _)) => true
+ | _ => false
+in
+ case find_first find_fun asms of
+ SOME (_ $ (_ $ (f $ a))) => SOME (f, a)
+ | _ => NONE
+end
+
+fun quot_true_simple_conv ctxt fnctn ctrm =
+ case (term_of ctrm) of
+ (Const (@{const_name Quot_True}, _) $ x) =>
+ let
+ val fx = fnctn x;
+ val thy = ProofContext.theory_of ctxt;
+ val cx = cterm_of thy x;
+ val cfx = cterm_of thy fx;
+ val cxt = ctyp_of thy (fastype_of x);
+ val cfxt = ctyp_of thy (fastype_of fx);
+ val thm = Drule.instantiate' [SOME cxt, SOME cfxt] [SOME cx, SOME cfx] @{thm QT_imp}
+ in
+ Conv.rewr_conv thm ctrm
+ end
+
+fun quot_true_conv ctxt fnctn ctrm =
+ case (term_of ctrm) of
+ (Const (@{const_name Quot_True}, _) $ _) =>
+ quot_true_simple_conv ctxt fnctn ctrm
+ | _ $ _ => Conv.comb_conv (quot_true_conv ctxt fnctn) ctrm
+ | Abs _ => Conv.abs_conv (fn (_, ctxt) => quot_true_conv ctxt fnctn) ctxt ctrm
+ | _ => Conv.all_conv ctrm
+
+fun quot_true_tac ctxt fnctn =
+ CONVERSION
+ ((Conv.params_conv ~1 (fn ctxt =>
+ (Conv.prems_conv ~1 (quot_true_conv ctxt fnctn)))) ctxt)
+
+fun dest_comb (f $ a) = (f, a)
+fun dest_bcomb ((_ $ l) $ r) = (l, r)
+
+fun unlam t =
+ case t of
+ (Abs a) => snd (Term.dest_abs a)
+ | _ => unlam (Abs("", domain_type (fastype_of t), (incr_boundvars 1 t) $ (Bound 0)))
+
+fun dest_fun_type (Type("fun", [T, S])) = (T, S)
+ | dest_fun_type _ = error "dest_fun_type"
+
+val bare_concl = HOLogic.dest_Trueprop o Logic.strip_assums_concl
+
+(* We apply apply_rsp only in case if the type needs lifting.
+ This is the case if the type of the data in the Quot_True
+ assumption is different from the corresponding type in the goal.
+*)
+val apply_rsp_tac =
+ Subgoal.FOCUS (fn {concl, asms, context,...} =>
+ let
+ val bare_concl = HOLogic.dest_Trueprop (term_of concl)
+ val qt_asm = find_qt_asm (map term_of asms)
+ in
+ case (bare_concl, qt_asm) of
+ (R2 $ (f $ x) $ (g $ y), SOME (qt_fun, qt_arg)) =>
+ if fastype_of qt_fun = fastype_of f
+ then no_tac
+ else
+ let
+ val ty_x = fastype_of x
+ val ty_b = fastype_of qt_arg
+ val ty_f = range_type (fastype_of f)
+ val thy = ProofContext.theory_of context
+ val ty_inst = map (SOME o (ctyp_of thy)) [ty_x, ty_b, ty_f]
+ val t_inst = map (SOME o (cterm_of thy)) [R2, f, g, x, y];
+ val inst_thm = Drule.instantiate' ty_inst
+ ([NONE, NONE, NONE] @ t_inst) @{thm apply_rsp}
+ in
+ (rtac inst_thm THEN' quotient_tac context) 1
+ end
+ | _ => no_tac
+ end)
+
+(* Instantiates and applies 'equals_rsp'. Since the theorem is
+ complex we rely on instantiation to tell us if it applies
+*)
+fun equals_rsp_tac R ctxt =
+let
+ val thy = ProofContext.theory_of ctxt
+in
+ case try (cterm_of thy) R of (* There can be loose bounds in R *)
+ SOME ctm =>
+ let
+ val ty = domain_type (fastype_of R)
+ in
+ case try (Drule.instantiate' [SOME (ctyp_of thy ty)]
+ [SOME (cterm_of thy R)]) @{thm equals_rsp} of
+ SOME thm => rtac thm THEN' quotient_tac ctxt
+ | NONE => K no_tac
+ end
+ | _ => K no_tac
+end
+
+fun rep_abs_rsp_tac ctxt =
+ SUBGOAL (fn (goal, i) =>
+ case (try bare_concl goal) of
+ SOME (rel $ _ $ (rep $ (abs $ _))) =>
+ let
+ val thy = ProofContext.theory_of ctxt;
+ val (ty_a, ty_b) = dest_fun_type (fastype_of abs);
+ val ty_inst = map (SOME o (ctyp_of thy)) [ty_a, ty_b];
+ in
+ case try (map (SOME o (cterm_of thy))) [rel, abs, rep] of
+ SOME t_inst =>
+ (case try (Drule.instantiate' ty_inst t_inst) @{thm rep_abs_rsp} of
+ SOME inst_thm => (rtac inst_thm THEN' quotient_tac ctxt) i
+ | NONE => no_tac)
+ | NONE => no_tac
+ end
+ | _ => no_tac)
+
+
+
+(* Injection means to prove that the regularised theorem implies
+ the abs/rep injected one.
+
+ The deterministic part:
+ - remove lambdas from both sides
+ - prove Ball/Bex/Babs equalities using ball_rsp, bex_rsp, babs_rsp
+ - prove Ball/Bex relations unfolding fun_rel_id
+ - reflexivity of equality
+ - prove equality of relations using equals_rsp
+ - use user-supplied RSP theorems
+ - solve 'relation of relations' goals using quot_rel_rsp
+ - remove rep_abs from the right side
+ (Lambdas under respects may have left us some assumptions)
+
+ Then in order:
+ - split applications of lifted type (apply_rsp)
+ - split applications of non-lifted type (cong_tac)
+ - apply extentionality
+ - assumption
+ - reflexivity of the relation
+*)
+fun injection_match_tac ctxt = SUBGOAL (fn (goal, i) =>
+(case (bare_concl goal) of
+ (* (R1 ===> R2) (%x...) (%x...) ----> [|R1 x y|] ==> R2 (...x) (...y) *)
+ (Const (@{const_name fun_rel}, _) $ _ $ _) $ (Abs _) $ (Abs _)
+ => rtac @{thm fun_rel_id} THEN' quot_true_tac ctxt unlam
+
+ (* (op =) (Ball...) (Ball...) ----> (op =) (...) (...) *)
+| (Const (@{const_name "op ="},_) $
+ (Const(@{const_name Ball},_) $ (Const (@{const_name Respects}, _) $ _) $ _) $
+ (Const(@{const_name Ball},_) $ (Const (@{const_name Respects}, _) $ _) $ _))
+ => rtac @{thm ball_rsp} THEN' dtac @{thm QT_all}
+
+ (* (R1 ===> op =) (Ball...) (Ball...) ----> [|R1 x y|] ==> (Ball...x) = (Ball...y) *)
+| (Const (@{const_name fun_rel}, _) $ _ $ _) $
+ (Const(@{const_name Ball},_) $ (Const (@{const_name Respects}, _) $ _) $ _) $
+ (Const(@{const_name Ball},_) $ (Const (@{const_name Respects}, _) $ _) $ _)
+ => rtac @{thm fun_rel_id} THEN' quot_true_tac ctxt unlam
+
+ (* (op =) (Bex...) (Bex...) ----> (op =) (...) (...) *)
+| Const (@{const_name "op ="},_) $
+ (Const(@{const_name Bex},_) $ (Const (@{const_name Respects}, _) $ _) $ _) $
+ (Const(@{const_name Bex},_) $ (Const (@{const_name Respects}, _) $ _) $ _)
+ => rtac @{thm bex_rsp} THEN' dtac @{thm QT_ex}
+
+ (* (R1 ===> op =) (Bex...) (Bex...) ----> [|R1 x y|] ==> (Bex...x) = (Bex...y) *)
+| (Const (@{const_name fun_rel}, _) $ _ $ _) $
+ (Const(@{const_name Bex},_) $ (Const (@{const_name Respects}, _) $ _) $ _) $
+ (Const(@{const_name Bex},_) $ (Const (@{const_name Respects}, _) $ _) $ _)
+ => rtac @{thm fun_rel_id} THEN' quot_true_tac ctxt unlam
+
+| (Const (@{const_name fun_rel}, _) $ _ $ _) $
+ (Const(@{const_name Bex1_rel},_) $ _) $ (Const(@{const_name Bex1_rel},_) $ _)
+ => rtac @{thm bex1_rel_rsp} THEN' quotient_tac ctxt
+
+| (_ $
+ (Const(@{const_name Babs},_) $ (Const (@{const_name Respects}, _) $ _) $ _) $
+ (Const(@{const_name Babs},_) $ (Const (@{const_name Respects}, _) $ _) $ _))
+ => rtac @{thm babs_rsp} THEN' RANGE [quotient_tac ctxt]
+
+| Const (@{const_name "op ="},_) $ (R $ _ $ _) $ (_ $ _ $ _) =>
+ (rtac @{thm refl} ORELSE'
+ (equals_rsp_tac R ctxt THEN' RANGE [
+ quot_true_tac ctxt (fst o dest_bcomb), quot_true_tac ctxt (snd o dest_bcomb)]))
+
+ (* reflexivity of operators arising from Cong_tac *)
+| Const (@{const_name "op ="},_) $ _ $ _ => rtac @{thm refl}
+
+ (* respectfulness of constants; in particular of a simple relation *)
+| _ $ (Const _) $ (Const _) (* fun_rel, list_rel, etc but not equality *)
+ => resolve_tac (rsp_rules_get ctxt) THEN_ALL_NEW quotient_tac ctxt
+
+ (* R (...) (Rep (Abs ...)) ----> R (...) (...) *)
+ (* observe fun_map *)
+| _ $ _ $ _
+ => (rtac @{thm quot_rel_rsp} THEN_ALL_NEW quotient_tac ctxt)
+ ORELSE' rep_abs_rsp_tac ctxt
+
+| _ => K no_tac
+) i)
+
+fun injection_step_tac ctxt rel_refl =
+ FIRST' [
+ injection_match_tac ctxt,
+
+ (* R (t $ ...) (t' $ ...) ----> apply_rsp provided type of t needs lifting *)
+ apply_rsp_tac ctxt THEN'
+ RANGE [quot_true_tac ctxt (fst o dest_comb), quot_true_tac ctxt (snd o dest_comb)],
+
+ (* (op =) (t $ ...) (t' $ ...) ----> Cong provided type of t does not need lifting *)
+ (* merge with previous tactic *)
+ Cong_Tac.cong_tac @{thm cong} THEN'
+ RANGE [quot_true_tac ctxt (fst o dest_comb), quot_true_tac ctxt (snd o dest_comb)],
+
+ (* (op =) (%x...) (%y...) ----> (op =) (...) (...) *)
+ rtac @{thm ext} THEN' quot_true_tac ctxt unlam,
+
+ (* resolving with R x y assumptions *)
+ atac,
+
+ (* reflexivity of the basic relations *)
+ (* R ... ... *)
+ resolve_tac rel_refl]
+
+fun injection_tac ctxt =
+let
+ val rel_refl = map (OF1 @{thm equivp_reflp}) (equiv_rules_get ctxt)
+in
+ injection_step_tac ctxt rel_refl
+end
+
+fun all_injection_tac ctxt =
+ REPEAT_ALL_NEW (injection_tac ctxt)
+
+
+
+(*** Cleaning of the Theorem ***)
+
+(* expands all fun_maps, except in front of the (bound) variables listed in xs *)
+fun fun_map_simple_conv xs ctrm =
+ case (term_of ctrm) of
+ ((Const (@{const_name "fun_map"}, _) $ _ $ _) $ h $ _) =>
+ if member (op=) xs h
+ then Conv.all_conv ctrm
+ else Conv.rewr_conv @{thm fun_map_def[THEN eq_reflection]} ctrm
+ | _ => Conv.all_conv ctrm
+
+fun fun_map_conv xs ctxt ctrm =
+ case (term_of ctrm) of
+ _ $ _ => (Conv.comb_conv (fun_map_conv xs ctxt) then_conv
+ fun_map_simple_conv xs) ctrm
+ | Abs _ => Conv.abs_conv (fn (x, ctxt) => fun_map_conv ((term_of x)::xs) ctxt) ctxt ctrm
+ | _ => Conv.all_conv ctrm
+
+fun fun_map_tac ctxt = CONVERSION (fun_map_conv [] ctxt)
+
+(* custom matching functions *)
+fun mk_abs u i t =
+ if incr_boundvars i u aconv t then Bound i else
+ case t of
+ t1 $ t2 => mk_abs u i t1 $ mk_abs u i t2
+ | Abs (s, T, t') => Abs (s, T, mk_abs u (i + 1) t')
+ | Bound j => if i = j then error "make_inst" else t
+ | _ => t
+
+fun make_inst lhs t =
+let
+ val _ $ (Abs (_, _, (_ $ ((f as Var (_, Type ("fun", [T, _]))) $ u)))) = lhs;
+ val _ $ (Abs (_, _, (_ $ g))) = t;
+in
+ (f, Abs ("x", T, mk_abs u 0 g))
+end
+
+fun make_inst_id lhs t =
+let
+ val _ $ (Abs (_, _, (f as Var (_, Type ("fun", [T, _]))) $ u)) = lhs;
+ val _ $ (Abs (_, _, g)) = t;
+in
+ (f, Abs ("x", T, mk_abs u 0 g))
+end
+
+(* Simplifies a redex using the 'lambda_prs' theorem.
+ First instantiates the types and known subterms.
+ Then solves the quotient assumptions to get Rep2 and Abs1
+ Finally instantiates the function f using make_inst
+ If Rep2 is an identity then the pattern is simpler and
+ make_inst_id is used
+*)
+fun lambda_prs_simple_conv ctxt ctrm =
+ case (term_of ctrm) of
+ (Const (@{const_name fun_map}, _) $ r1 $ a2) $ (Abs _) =>
+ let
+ val thy = ProofContext.theory_of ctxt
+ val (ty_b, ty_a) = dest_fun_type (fastype_of r1)
+ val (ty_c, ty_d) = dest_fun_type (fastype_of a2)
+ val tyinst = map (SOME o (ctyp_of thy)) [ty_a, ty_b, ty_c, ty_d]
+ val tinst = [NONE, NONE, SOME (cterm_of thy r1), NONE, SOME (cterm_of thy a2)]
+ val thm1 = Drule.instantiate' tyinst tinst @{thm lambda_prs[THEN eq_reflection]}
+ val thm2 = solve_quotient_assm ctxt (solve_quotient_assm ctxt thm1)
+ val thm3 = MetaSimplifier.rewrite_rule @{thms id_apply[THEN eq_reflection]} thm2
+ val (insp, inst) =
+ if ty_c = ty_d
+ then make_inst_id (term_of (Thm.lhs_of thm3)) (term_of ctrm)
+ else make_inst (term_of (Thm.lhs_of thm3)) (term_of ctrm)
+ val thm4 = Drule.instantiate ([], [(cterm_of thy insp, cterm_of thy inst)]) thm3
+ in
+ Conv.rewr_conv thm4 ctrm
+ end
+ | _ => Conv.all_conv ctrm
+
+fun lambda_prs_conv ctxt = More_Conv.top_conv lambda_prs_simple_conv ctxt
+fun lambda_prs_tac ctxt = CONVERSION (lambda_prs_conv ctxt)
+
+
+(* Cleaning consists of:
+
+ 1. unfolding of ---> in front of everything, except
+ bound variables (this prevents lambda_prs from
+ becoming stuck)
+
+ 2. simplification with lambda_prs
+
+ 3. simplification with:
+
+ - Quotient_abs_rep Quotient_rel_rep
+ babs_prs all_prs ex_prs ex1_prs
+
+ - id_simps and preservation lemmas and
+
+ - symmetric versions of the definitions
+ (that is definitions of quotient constants
+ are folded)
+
+ 4. test for refl
+*)
+fun clean_tac lthy =
+let
+ val defs = map (symmetric o #def) (qconsts_dest lthy)
+ val prs = prs_rules_get lthy
+ val ids = id_simps_get lthy
+ val thms = @{thms Quotient_abs_rep Quotient_rel_rep babs_prs all_prs ex_prs ex1_prs} @ ids @ prs @ defs
+
+ val ss = (mk_minimal_ss lthy) addsimps thms addSolver quotient_solver
+in
+ EVERY' [fun_map_tac lthy,
+ lambda_prs_tac lthy,
+ simp_tac ss,
+ TRY o rtac refl]
+end
+
+
+
+(** Tactic for Generalising Free Variables in a Goal **)
+
+fun inst_spec ctrm =
+ Drule.instantiate' [SOME (ctyp_of_term ctrm)] [NONE, SOME ctrm] @{thm spec}
+
+fun inst_spec_tac ctrms =
+ EVERY' (map (dtac o inst_spec) ctrms)
+
+fun all_list xs trm =
+ fold (fn (x, T) => fn t' => HOLogic.mk_all (x, T, t')) xs trm
+
+fun apply_under_Trueprop f =
+ HOLogic.dest_Trueprop #> f #> HOLogic.mk_Trueprop
+
+fun gen_frees_tac ctxt =
+ SUBGOAL (fn (concl, i) =>
+ let
+ val thy = ProofContext.theory_of ctxt
+ val vrs = Term.add_frees concl []
+ val cvrs = map (cterm_of thy o Free) vrs
+ val concl' = apply_under_Trueprop (all_list vrs) concl
+ val goal = Logic.mk_implies (concl', concl)
+ val rule = Goal.prove ctxt [] [] goal
+ (K (EVERY1 [inst_spec_tac (rev cvrs), atac]))
+ in
+ rtac rule i
+ end)
+
+
+(** The General Shape of the Lifting Procedure **)
+
+(* - A is the original raw theorem
+ - B is the regularized theorem
+ - C is the rep/abs injected version of B
+ - D is the lifted theorem
+
+ - 1st prem is the regularization step
+ - 2nd prem is the rep/abs injection step
+ - 3rd prem is the cleaning part
+
+ the Quot_True premise in 2nd records the lifted theorem
+*)
+val lifting_procedure_thm =
+ @{lemma "[|A;
+ A --> B;
+ Quot_True D ==> B = C;
+ C = D|] ==> D"
+ by (simp add: Quot_True_def)}
+
+fun lift_match_error ctxt msg rtrm qtrm =
+let
+ val rtrm_str = Syntax.string_of_term ctxt rtrm
+ val qtrm_str = Syntax.string_of_term ctxt qtrm
+ val msg = cat_lines [enclose "[" "]" msg, "The quotient theorem", qtrm_str,
+ "", "does not match with original theorem", rtrm_str]
+in
+ error msg
+end
+
+fun procedure_inst ctxt rtrm qtrm =
+let
+ val thy = ProofContext.theory_of ctxt
+ val rtrm' = HOLogic.dest_Trueprop rtrm
+ val qtrm' = HOLogic.dest_Trueprop qtrm
+ val reg_goal = regularize_trm_chk ctxt (rtrm', qtrm')
+ handle (LIFT_MATCH msg) => lift_match_error ctxt msg rtrm qtrm
+ val inj_goal = inj_repabs_trm_chk ctxt (reg_goal, qtrm')
+ handle (LIFT_MATCH msg) => lift_match_error ctxt msg rtrm qtrm
+in
+ Drule.instantiate' []
+ [SOME (cterm_of thy rtrm'),
+ SOME (cterm_of thy reg_goal),
+ NONE,
+ SOME (cterm_of thy inj_goal)] lifting_procedure_thm
+end
+
+(* the tactic leaves three subgoals to be proved *)
+fun procedure_tac ctxt rthm =
+ ObjectLogic.full_atomize_tac
+ THEN' gen_frees_tac ctxt
+ THEN' SUBGOAL (fn (goal, i) =>
+ let
+ val rthm' = atomize_thm rthm
+ val rule = procedure_inst ctxt (prop_of rthm') goal
+ in
+ (rtac rule THEN' rtac rthm') i
+ end)
+
+
+(* Automatic Proofs *)
+
+val msg1 = "The regularize proof failed."
+val msg2 = cat_lines ["The injection proof failed.",
+ "This is probably due to missing respects lemmas.",
+ "Try invoking the injection method manually to see",
+ "which lemmas are missing."]
+val msg3 = "The cleaning proof failed."
+
+fun lift_tac ctxt rthms =
+let
+ fun mk_tac rthm =
+ procedure_tac ctxt rthm
+ THEN' RANGE_WARN
+ [(regularize_tac ctxt, msg1),
+ (all_injection_tac ctxt, msg2),
+ (clean_tac ctxt, msg3)]
+in
+ simp_tac (mk_minimal_ss ctxt) (* unfolding multiple &&& *)
+ THEN' RANGE (map mk_tac rthms)
+end
+
+(* An Attribute which automatically constructs the qthm *)
+fun lifted_attrib_aux context thm =
+let
+ val ctxt = Context.proof_of context
+ val ((_, [thm']), ctxt') = Variable.import false [thm] ctxt
+ val goal = (quotient_lift_all ctxt' o prop_of) thm'
+in
+ Goal.prove ctxt' [] [] goal (K (lift_tac ctxt' [thm] 1))
+ |> singleton (ProofContext.export ctxt' ctxt)
+end;
+
+val lifted_attrib = Thm.rule_attribute lifted_attrib_aux
+
+end; (* structure *)