# HG changeset patch # User paulson # Date 863005882 -7200 # Node ID 3f0ab2c306f75b84996c9796711185c6f1883437 # Parent 1c0dfa7ebb72adf58dbc174212efbfc9f67c98f6 Moved induction examples to directory Induct diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/IsaMakefile --- a/src/HOL/IsaMakefile Wed May 07 13:50:52 1997 +0200 +++ b/src/HOL/IsaMakefile Wed May 07 13:51:22 1997 +0200 @@ -41,6 +41,17 @@ #### Tests and examples +## Inductive definitions: simple examples + +INDUCT_FILES = Perm Comb Mutil SList LList LFilter Acc PropLog Term Simult + +INDUCT_FILES = Induct/ROOT.ML \ + $(INDUCT_NAMES:%=Induct/%.thy) $(INDUCT_NAMES:%=Induct/%.ML) + +Induct: $(OUT)/HOL $(INDUCT_FILES) + @$(ISATOOL) usedir $(OUT)/HOL Induct + + ## IMP-semantics example IMP_NAMES = Expr Com Natural Transition Denotation Hoare VC @@ -185,8 +196,7 @@ ## Miscellaneous examples -EX_NAMES = String BT Perm Comb InSort Qsort LexProd Puzzle Mutil \ - Primes NatSum SList LList LFilter Acc PropLog Term Simult MT +EX_NAMES = String BT InSort Qsort LexProd Puzzle Primes NatSum MT EX_FILES = ex/ROOT.ML ex/cla.ML ex/meson.ML ex/mesontest.ML ex/rel.ML \ ex/set.ML $(EX_NAMES:%=ex/%.thy) $(EX_NAMES:%=ex/%.ML) @@ -198,7 +208,8 @@ ## Full test test: $(OUT)/HOL \ - TFL IMP Hoare Lex Integ Auth Subst Lambda W0 MiniML IOA AxClasses Quot ex + TFL Induct IMP Hoare Lex Integ Auth Subst Lambda \ + W0 MiniML IOA AxClasses Quot ex echo 'Test examples ran successfully' > test diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/Makefile --- a/src/HOL/Makefile Wed May 07 13:50:52 1997 +0200 +++ b/src/HOL/Makefile Wed May 07 13:51:22 1997 +0200 @@ -88,6 +88,21 @@ else echo 'exit_use_dir"../TFL";quit();' | $(LOGIC); \ fi + +## Inductive definitions: simple examples + +INDUCT_FILES = Perm Comb Mutil SList LList LFilter Acc PropLog Term Simult + +INDUCT_FILES = Induct/ROOT.ML \ + $(INDUCT_NAMES:%=Induct/%.thy) $(INDUCT_NAMES:%=Induct/%.ML) + +Induct: $(BIN)/HOL $(INDUCT_FILES) + @if [ "$${MAKE_HTML-undefined}" != "undefined" ]; \ + then echo 'make_html := true; exit_use_dir"Induct";quit();' | $(LOGIC); \ + else echo 'exit_use_dir"Induct";quit();' | $(LOGIC); \ + fi + + ##IMP-semantics example IMP_NAMES = Expr Com Natural Transition Denotation Hoare VC IMP_FILES = IMP/ROOT.ML $(IMP_NAMES:%=IMP/%.thy) $(IMP_NAMES:%=IMP/%.ML) @@ -201,8 +216,7 @@ fi ##Miscellaneous examples -EX_NAMES = String BT Perm Comb InSort Qsort LexProd Puzzle Mutil \ - Primes NatSum SList LList LFilter Acc PropLog Term Simult MT +EX_NAMES = String BT InSort Qsort LexProd Puzzle Primes NatSum MT EX_FILES = ex/ROOT.ML ex/cla.ML ex/meson.ML ex/mesontest.ML ex/rel.ML \ ex/set.ML $(EX_NAMES:%=ex/%.thy) $(EX_NAMES:%=ex/%.ML) @@ -214,7 +228,9 @@ fi #Full test. -test: $(BIN)/HOL TFL IMP Hoare Lex Integ Auth Subst Lambda MiniML ex +test: $(BIN)/HOL \ + TFL Induct IMP Hoare Lex Integ Auth Subst Lambda \ + W0 MiniML IOA AxClasses Quot ex echo 'Test examples ran successfully' > test .PRECIOUS: $(BIN)/Pure $(BIN)/HOL diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/README.html --- a/src/HOL/README.html Wed May 07 13:50:52 1997 +0200 +++ b/src/HOL/README.html Wed May 07 13:51:22 1997 +0200 @@ -31,11 +31,14 @@
IMP
mechanization of a large part of a semantics text by Glynn Winskel +
Induct +
examples of (co)inductive definitions +
Integ
a theory of the integers including efficient integer calculations
IOA -
extended example of Input/Output Automata (takes a long time to run!) +
extended example of Input/Output Automata
Lambda
a proof of the Church-Rosser theorem for lambda-calculus diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/Acc.ML --- a/src/HOL/ex/Acc.ML Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,63 +0,0 @@ -(* Title: HOL/ex/Acc - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1994 University of Cambridge - -Inductive definition of acc(r) - -See Ch. Paulin-Mohring, Inductive Definitions in the System Coq. -Research Report 92-49, LIP, ENS Lyon. Dec 1992. -*) - -open Acc; - -(*The intended introduction rule*) -val prems = goal Acc.thy - "[| !!b. (b,a):r ==> b: acc(r) |] ==> a: acc(r)"; -by (fast_tac (!claset addIs (prems @ - map (rewrite_rule [pred_def]) acc.intrs)) 1); -qed "accI"; - -goal Acc.thy "!!a b r. [| b: acc(r); (a,b): r |] ==> a: acc(r)"; -by (etac acc.elim 1); -by (rewtac pred_def); -by (Fast_tac 1); -qed "acc_downward"; - -val [major,indhyp] = goal Acc.thy - "[| a : acc(r); \ -\ !!x. [| x: acc(r); ALL y. (y,x):r --> P(y) |] ==> P(x) \ -\ |] ==> P(a)"; -by (rtac (major RS acc.induct) 1); -by (rtac indhyp 1); -by (resolve_tac acc.intrs 1); -by (rewtac pred_def); -by (Fast_tac 2); -by (etac (Int_lower1 RS Pow_mono RS subsetD) 1); -qed "acc_induct"; - - -val [major] = goal Acc.thy "r <= (acc r) Times (acc r) ==> wf(r)"; -by (rtac (major RS wfI) 1); -by (etac acc.induct 1); -by (rewtac pred_def); -by (Fast_tac 1); -qed "acc_wfI"; - -val [major] = goal Acc.thy "wf(r) ==> ALL x. (x,y): r | (y,x):r --> y: acc(r)"; -by (rtac (major RS wf_induct) 1); -by (rtac (impI RS allI) 1); -by (rtac accI 1); -by (Fast_tac 1); -qed "acc_wfD_lemma"; - -val [major] = goal Acc.thy "wf(r) ==> r <= (acc r) Times (acc r)"; -by (rtac subsetI 1); -by (res_inst_tac [("p", "x")] PairE 1); -by (fast_tac (!claset addSIs [SigmaI, - major RS acc_wfD_lemma RS spec RS mp]) 1); -qed "acc_wfD"; - -goal Acc.thy "wf(r) = (r <= (acc r) Times (acc r))"; -by (EVERY1 [rtac iffI, etac acc_wfD, etac acc_wfI]); -qed "wf_acc_iff"; diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/Acc.thy --- a/src/HOL/ex/Acc.thy Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,26 +0,0 @@ -(* Title: HOL/ex/Acc.thy - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1994 University of Cambridge - -Inductive definition of acc(r) - -See Ch. Paulin-Mohring, Inductive Definitions in the System Coq. -Research Report 92-49, LIP, ENS Lyon. Dec 1992. -*) - -Acc = WF + - -constdefs - pred :: "['b, ('a * 'b)set] => 'a set" (*Set of predecessors*) - "pred x r == {y. (y,x):r}" - -consts - acc :: "('a * 'a)set => 'a set" (*Accessible part*) - -inductive "acc(r)" - intrs - pred "pred a r: Pow(acc(r)) ==> a: acc(r)" - monos "[Pow_mono]" - -end diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/Comb.ML --- a/src/HOL/ex/Comb.ML Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,179 +0,0 @@ -(* Title: HOL/ex/comb.ML - ID: $Id$ - Author: Lawrence C Paulson - Copyright 1996 University of Cambridge - -Combinatory Logic example: the Church-Rosser Theorem -Curiously, combinators do not include free variables. - -Example taken from - J. Camilleri and T. F. Melham. - Reasoning with Inductively Defined Relations in the HOL Theorem Prover. - Report 265, University of Cambridge Computer Laboratory, 1992. - -HOL system proofs may be found in -/usr/groups/theory/hvg-aftp/contrib/rule-induction/cl.ml -*) - -open Comb; - -(*** Reflexive/Transitive closure preserves the Church-Rosser property - So does the Transitive closure; use r_into_trancl instead of rtrancl_refl -***) - -val [_, spec_mp] = [spec] RL [mp]; - -(*Strip lemma. The induction hyp is all but the last diamond of the strip.*) -goalw Comb.thy [diamond_def] - "!!r. [| diamond(r); (x,y):r^* |] ==> \ -\ ALL y'. (x,y'):r --> (EX z. (y',z): r^* & (y,z): r)"; -by (etac rtrancl_induct 1); -by (Blast_tac 1); -by (slow_best_tac (set_cs addIs [r_into_rtrancl RSN (2, rtrancl_trans)] - addSDs [spec_mp]) 1); -val diamond_strip_lemmaE = result() RS spec RS mp RS exE; - -val [major] = goal Comb.thy "diamond(r) ==> diamond(r^*)"; -by (rewtac diamond_def); (*unfold only in goal, not in premise!*) -by (rtac (impI RS allI RS allI) 1); -by (etac rtrancl_induct 1); -by (Blast_tac 1); -by (slow_best_tac (*Seems to be a brittle, undirected search*) - (set_cs addIs [r_into_rtrancl RSN (2, rtrancl_trans)] - addEs [major RS diamond_strip_lemmaE]) 1); -qed "diamond_rtrancl"; - - -(*** Results about Contraction ***) - -(*Derive a case for each combinator constructor*) -val K_contractE = contract.mk_cases comb.simps "K -1-> z"; -val S_contractE = contract.mk_cases comb.simps "S -1-> z"; -val Ap_contractE = contract.mk_cases comb.simps "x#y -1-> z"; - -AddSIs [contract.K, contract.S]; -AddIs [contract.Ap1, contract.Ap2]; -AddSEs [K_contractE, S_contractE, Ap_contractE]; -Unsafe_Addss (!simpset); - -goalw Comb.thy [I_def] "!!z. I -1-> z ==> P"; -by (Blast_tac 1); -qed "I_contract_E"; -AddSEs [I_contract_E]; - -goal Comb.thy "!!x z. K#x -1-> z ==> (EX x'. z = K#x' & x -1-> x')"; -by (Blast_tac 1); -qed "K1_contractD"; -AddSEs [K1_contractD]; - -goal Comb.thy "!!x z. x ---> y ==> x#z ---> y#z"; -by (etac rtrancl_induct 1); -by (ALLGOALS (blast_tac (!claset addIs [r_into_rtrancl, rtrancl_trans]))); -qed "Ap_reduce1"; - -goal Comb.thy "!!x z. x ---> y ==> z#x ---> z#y"; -by (etac rtrancl_induct 1); -by (ALLGOALS (blast_tac (!claset addIs [r_into_rtrancl, rtrancl_trans]))); -qed "Ap_reduce2"; - -(** Counterexample to the diamond property for -1-> **) - -goal Comb.thy "K#I#(I#I) -1-> I"; -by (rtac contract.K 1); -qed "KIII_contract1"; - -goalw Comb.thy [I_def] "K#I#(I#I) -1-> K#I#((K#I)#(K#I))"; -by (Blast_tac 1); -qed "KIII_contract2"; - -goal Comb.thy "K#I#((K#I)#(K#I)) -1-> I"; -by (Blast_tac 1); -qed "KIII_contract3"; - -goalw Comb.thy [diamond_def] "~ diamond(contract)"; -by (blast_tac (!claset addIs [KIII_contract1,KIII_contract2,KIII_contract3]) 1); -qed "not_diamond_contract"; - - - -(*** Results about Parallel Contraction ***) - -(*Derive a case for each combinator constructor*) -val K_parcontractE = parcontract.mk_cases comb.simps "K =1=> z"; -val S_parcontractE = parcontract.mk_cases comb.simps "S =1=> z"; -val Ap_parcontractE = parcontract.mk_cases comb.simps "x#y =1=> z"; - -AddIs parcontract.intrs; -AddSEs [K_parcontractE, S_parcontractE,Ap_parcontractE]; -Unsafe_Addss (!simpset); - -(*** Basic properties of parallel contraction ***) - -goal Comb.thy "!!x z. K#x =1=> z ==> (EX x'. z = K#x' & x =1=> x')"; -by (Blast_tac 1); -qed "K1_parcontractD"; -AddSDs [K1_parcontractD]; - -goal Comb.thy "!!x z. S#x =1=> z ==> (EX x'. z = S#x' & x =1=> x')"; -by (Blast_tac 1); -qed "S1_parcontractD"; -AddSDs [S1_parcontractD]; - -goal Comb.thy - "!!x y z. S#x#y =1=> z ==> (EX x' y'. z = S#x'#y' & x =1=> x' & y =1=> y')"; -by (Blast_tac 1); -qed "S2_parcontractD"; -AddSDs [S2_parcontractD]; - -(*The rules above are not essential but make proofs much faster*) - - -(*Church-Rosser property for parallel contraction*) -goalw Comb.thy [diamond_def] "diamond parcontract"; -by (rtac (impI RS allI RS allI) 1); -by (etac parcontract.induct 1 THEN prune_params_tac); -by (Step_tac 1); -by (ALLGOALS Blast_tac); -qed "diamond_parcontract"; - - -(*** Equivalence of x--->y and x===>y ***) - -goal Comb.thy "contract <= parcontract"; -by (rtac subsetI 1); -by (split_all_tac 1); -by (etac contract.induct 1); -by (ALLGOALS Blast_tac); -qed "contract_subset_parcontract"; - -(*Reductions: simply throw together reflexivity, transitivity and - the one-step reductions*) - -AddIs [Ap_reduce1, Ap_reduce2, r_into_rtrancl, rtrancl_trans]; - -(*Example only: not used*) -goalw Comb.thy [I_def] "I#x ---> x"; -by (Blast_tac 1); -qed "reduce_I"; - -goal Comb.thy "parcontract <= contract^*"; -by (rtac subsetI 1); -by (split_all_tac 1); -by (etac parcontract.induct 1 THEN prune_params_tac); -by (ALLGOALS Blast_tac); -qed "parcontract_subset_reduce"; - -goal Comb.thy "contract^* = parcontract^*"; -by (REPEAT - (resolve_tac [equalityI, - contract_subset_parcontract RS rtrancl_mono, - parcontract_subset_reduce RS rtrancl_subset_rtrancl] 1)); -qed "reduce_eq_parreduce"; - -goal Comb.thy "diamond(contract^*)"; -by (simp_tac (!simpset addsimps [reduce_eq_parreduce, diamond_rtrancl, - diamond_parcontract]) 1); -qed "diamond_reduce"; - - -writeln"Reached end of file."; diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/Comb.thy --- a/src/HOL/ex/Comb.thy Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,74 +0,0 @@ -(* Title: HOL/ex/Comb.thy - ID: $Id$ - Author: Lawrence C Paulson - Copyright 1996 University of Cambridge - -Combinatory Logic example: the Church-Rosser Theorem -Curiously, combinators do not include free variables. - -Example taken from - J. Camilleri and T. F. Melham. - Reasoning with Inductively Defined Relations in the HOL Theorem Prover. - Report 265, University of Cambridge Computer Laboratory, 1992. -*) - - -Comb = Trancl + - -(** Datatype definition of combinators S and K, with infixed application **) -datatype comb = K - | S - | "#" comb comb (infixl 90) - -(** Inductive definition of contractions, -1-> - and (multi-step) reductions, ---> -**) -consts - contract :: "(comb*comb) set" - "-1->" :: [comb,comb] => bool (infixl 50) - "--->" :: [comb,comb] => bool (infixl 50) - -translations - "x -1-> y" == "(x,y) : contract" - "x ---> y" == "(x,y) : contract^*" - -inductive contract - intrs - K "K#x#y -1-> x" - S "S#x#y#z -1-> (x#z)#(y#z)" - Ap1 "x-1->y ==> x#z -1-> y#z" - Ap2 "x-1->y ==> z#x -1-> z#y" - - -(** Inductive definition of parallel contractions, =1=> - and (multi-step) parallel reductions, ===> -**) -consts - parcontract :: "(comb*comb) set" - "=1=>" :: [comb,comb] => bool (infixl 50) - "===>" :: [comb,comb] => bool (infixl 50) - -translations - "x =1=> y" == "(x,y) : parcontract" - "x ===> y" == "(x,y) : parcontract^*" - -inductive parcontract - intrs - refl "x =1=> x" - K "K#x#y =1=> x" - S "S#x#y#z =1=> (x#z)#(y#z)" - Ap "[| x=1=>y; z=1=>w |] ==> x#z =1=> y#w" - - -(*Misc definitions*) -constdefs - I :: comb - "I == S#K#K" - - (*confluence; Lambda/Commutation treats this more abstractly*) - diamond :: "('a * 'a)set => bool" - "diamond(r) == ALL x y. (x,y):r --> - (ALL y'. (x,y'):r --> - (EX z. (y,z):r & (y',z) : r))" - -end diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/LFilter.ML --- a/src/HOL/ex/LFilter.ML Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,341 +0,0 @@ -(* Title: HOL/ex/LFilter - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1997 University of Cambridge - -The "filter" functional for coinductive lists - --defined by a combination of induction and coinduction -*) - -open LFilter; - - -(*** findRel: basic laws ****) - -val findRel_LConsE = - findRel.mk_cases [LCons_LCons_eq] "(LCons x l, l'') : findRel p"; - -AddSEs [findRel_LConsE]; - - -goal thy "!!p. (l,l'): findRel p ==> (l,l''): findRel p --> l'' = l'"; -by (etac findRel.induct 1); -by (Blast_tac 1); -by (Blast_tac 1); -qed_spec_mp "findRel_functional"; - -goal thy "!!p. (l,l'): findRel p ==> EX x l''. l' = LCons x l'' & p x"; -by (etac findRel.induct 1); -by (Blast_tac 1); -by (Blast_tac 1); -qed_spec_mp "findRel_imp_LCons"; - -goal thy "!!p. (LNil,l): findRel p ==> R"; -by (blast_tac (!claset addEs [findRel.elim]) 1); -qed "findRel_LNil"; - -AddSEs [findRel_LNil]; - - -(*** Properties of Domain (findRel p) ***) - -goal thy "!!p. LCons x l : Domain(findRel p) = (p x | l : Domain(findRel p))"; -by (case_tac "p x" 1); -by (ALLGOALS (blast_tac (!claset addIs findRel.intrs))); -qed "LCons_Domain_findRel"; - -Addsimps [LCons_Domain_findRel]; - -val major::prems = -goal thy "[| l: Domain (findRel p); \ -\ !!x l'. [| (l, LCons x l') : findRel p; p x |] ==> Q \ -\ |] ==> Q"; -by (rtac (major RS DomainE) 1); -by (forward_tac [findRel_imp_LCons] 1); -by (REPEAT (eresolve_tac [exE,conjE] 1)); -by (hyp_subst_tac 1); -by (REPEAT (ares_tac prems 1)); -qed "Domain_findRelE"; - -val prems = goal thy - "[| !!x. p x ==> q x |] ==> Domain (findRel p) <= Domain (findRel q)"; -by (Step_tac 1); -by (etac findRel.induct 1); -by (blast_tac (!claset addIs (findRel.intrs@prems)) 1); -by (blast_tac (!claset addIs findRel.intrs) 1); -qed "Domain_findRel_mono"; - - -(*** find: basic equations ***) - -goalw thy [find_def] "find p LNil = LNil"; -by (blast_tac (!claset addIs [select_equality]) 1); -qed "find_LNil"; - -goalw thy [find_def] "!!p. (l,l') : findRel p ==> find p l = l'"; -by (blast_tac (!claset addIs [select_equality] addDs [findRel_functional]) 1); -qed "findRel_imp_find"; - -goal thy "!!p. p x ==> find p (LCons x l) = LCons x l"; -by (blast_tac (!claset addIs (findRel_imp_find::findRel.intrs)) 1); -qed "find_LCons_found"; - -goalw thy [find_def] "!!p. l ~: Domain(findRel p) ==> find p l = LNil"; -by (blast_tac (!claset addIs [select_equality]) 1); -qed "diverge_find_LNil"; - -Addsimps [diverge_find_LNil]; - -goal thy "!!p. ~ (p x) ==> find p (LCons x l) = find p l"; -by (case_tac "LCons x l : Domain(findRel p)" 1); -by (Asm_full_simp_tac 2); -by (Step_tac 1); -by (asm_simp_tac (!simpset addsimps [findRel_imp_find]) 1); -by (blast_tac (!claset addIs (findRel_imp_find::findRel.intrs)) 1); -qed "find_LCons_seek"; - -goal thy "find p (LCons x l) = (if p x then LCons x l else find p l)"; -by (asm_simp_tac (!simpset addsimps [find_LCons_found, find_LCons_seek] - setloop split_tac[expand_if]) 1); -qed "find_LCons"; - - - -(*** lfilter: basic equations ***) - -goal thy "lfilter p LNil = LNil"; -by (rtac (lfilter_def RS def_llist_corec RS trans) 1); -by (simp_tac (!simpset addsimps [find_LNil]) 1); -qed "lfilter_LNil"; - -goal thy "!!p. l ~: Domain(findRel p) ==> lfilter p l = LNil"; -by (rtac (lfilter_def RS def_llist_corec RS trans) 1); -by (Asm_simp_tac 1); -qed "diverge_lfilter_LNil"; - - -goal thy "!!p. p x ==> lfilter p (LCons x l) = LCons x (lfilter p l)"; -by (rtac (lfilter_def RS def_llist_corec RS trans) 1); -by (asm_simp_tac (!simpset addsimps [find_LCons_found]) 1); -qed "lfilter_LCons_found"; - - -goal thy "!!p. (l, LCons x l') : findRel p \ -\ ==> lfilter p l = LCons x (lfilter p l')"; -by (rtac (lfilter_def RS def_llist_corec RS trans) 1); -by (asm_simp_tac (!simpset addsimps [findRel_imp_find]) 1); -qed "findRel_imp_lfilter"; - -goal thy "!!p. ~ (p x) ==> lfilter p (LCons x l) = lfilter p l"; -by (rtac (lfilter_def RS def_llist_corec RS trans) 1); -by (case_tac "LCons x l : Domain(findRel p)" 1); -by (asm_full_simp_tac (!simpset addsimps [diverge_lfilter_LNil]) 2); -by (etac Domain_findRelE 1); -by (safe_tac (!claset delrules [conjI])); -by (asm_full_simp_tac - (!simpset addsimps [findRel_imp_lfilter, findRel_imp_find, - find_LCons_seek]) 1); -qed "lfilter_LCons_seek"; - - -goal thy "lfilter p (LCons x l) = \ -\ (if p x then LCons x (lfilter p l) else lfilter p l)"; -by (asm_simp_tac (!simpset addsimps [lfilter_LCons_found, lfilter_LCons_seek] - setloop split_tac[expand_if]) 1); -qed "lfilter_LCons"; - -AddSIs [llistD_Fun_LNil_I, llistD_Fun_LCons_I]; -Addsimps [lfilter_LNil, lfilter_LCons]; - - -goal thy "!!p. lfilter p l = LNil ==> l ~: Domain(findRel p)"; -by (rtac notI 1); -by (etac Domain_findRelE 1); -by (etac rev_mp 1); -by (asm_simp_tac (!simpset addsimps [findRel_imp_lfilter]) 1); -qed "lfilter_eq_LNil"; - - -goal thy "!!p. lfilter p l = LCons x l' --> \ -\ (EX l''. l' = lfilter p l'' & (l, LCons x l'') : findRel p)"; -by (stac (lfilter_def RS def_llist_corec) 1); -by (case_tac "l : Domain(findRel p)" 1); -by (etac Domain_findRelE 1); -by (Asm_simp_tac 2); -by (asm_simp_tac (!simpset addsimps [findRel_imp_find]) 1); -by (Blast_tac 1); -qed_spec_mp "lfilter_eq_LCons"; - - -goal thy "lfilter p l = LNil | \ -\ (EX y l'. lfilter p l = LCons y (lfilter p l') & p y)"; -by (case_tac "l : Domain(findRel p)" 1); -by (asm_simp_tac (!simpset addsimps [diverge_lfilter_LNil]) 2); -by (blast_tac (!claset addSEs [Domain_findRelE] - addIs [findRel_imp_lfilter]) 1); -qed "lfilter_cases"; - - -(*** lfilter: simple facts by coinduction ***) - -goal thy "lfilter (%x.True) l = l"; -by (res_inst_tac [("l","l")] llist_fun_equalityI 1); -by (ALLGOALS Simp_tac); -by (Blast_tac 1); -qed "lfilter_K_True"; - -goal thy "lfilter p (lfilter p l) = lfilter p l"; -by (res_inst_tac [("l","l")] llist_fun_equalityI 1); -by (ALLGOALS (simp_tac (!simpset setloop split_tac[expand_if]))); -by (Step_tac 1); -(*Cases: p x is true or false*) -by (Blast_tac 1); -by (rtac (lfilter_cases RS disjE) 1); -by (etac ssubst 1); -by (Auto_tac()); -qed "lfilter_idem"; - - -(*** Numerous lemmas required to prove lfilter_conj: - lfilter p (lfilter q l) = lfilter (%x. p x & q x) l - ***) - -goal thy "!!p. (l,l') : findRel q \ -\ ==> l' = LCons x l'' --> p x --> (l,l') : findRel (%x. p x & q x)"; -by (etac findRel.induct 1); -by (blast_tac (!claset addIs findRel.intrs) 1); -by (blast_tac (!claset addIs findRel.intrs) 1); -qed_spec_mp "findRel_conj_lemma"; - -val findRel_conj = refl RSN (2, findRel_conj_lemma); - -goal thy "!!p. (l,l'') : findRel (%x. p x & q x) \ -\ ==> (l, LCons x l') : findRel q --> ~ p x \ -\ --> l' : Domain (findRel (%x. p x & q x))"; -by (etac findRel.induct 1); -by (Auto_tac()); -qed_spec_mp "findRel_not_conj_Domain"; - - -goal thy "!!p. (l,lxx) : findRel q ==> \ -\ lxx = LCons x lx --> (lx,lz) : findRel(%x. p x & q x) --> ~ p x \ -\ --> (l,lz) : findRel (%x. p x & q x)"; -by (etac findRel.induct 1); -by (ALLGOALS (blast_tac (!claset addIs findRel.intrs))); -qed_spec_mp "findRel_conj2"; - - -goal thy "!!p. (lx,ly) : findRel p \ -\ ==> ALL l. lx = lfilter q l \ -\ --> l : Domain (findRel(%x. p x & q x))"; -by (etac findRel.induct 1); -by (blast_tac (!claset addSDs [sym RS lfilter_eq_LCons] - addIs [findRel_conj]) 1); -by (Auto_tac()); -by (dtac (sym RS lfilter_eq_LCons) 1); -by (Auto_tac()); -by (dtac spec 1); -by (dtac (refl RS rev_mp) 1); -by (blast_tac (!claset addIs [findRel_conj2]) 1); -qed_spec_mp "findRel_lfilter_Domain_conj"; - - -goal thy "!!p. (l,l'') : findRel(%x. p x & q x) \ -\ ==> l'' = LCons y l' --> \ -\ (lfilter q l, LCons y (lfilter q l')) : findRel p"; -by (etac findRel.induct 1); -by (ALLGOALS (asm_simp_tac (!simpset setloop split_tac[expand_if]))); -by (ALLGOALS (blast_tac (!claset addIs findRel.intrs))); -qed_spec_mp "findRel_conj_lfilter"; - - - -goal thy "(lfilter p (lfilter q l), lfilter (%x. p x & q x) l) \ -\ : llistD_Fun (range \ -\ (%u. (lfilter p (lfilter q u), \ -\ lfilter (%x. p x & q x) u)))"; -by (case_tac "l : Domain(findRel q)" 1); -by (subgoal_tac "l ~: Domain (findRel (%x. p x & q x))" 2); -by (blast_tac (!claset addIs [impOfSubs Domain_findRel_mono]) 3); -(*There are no qs in l: both lists are LNil*) -by (asm_simp_tac (!simpset addsimps [diverge_lfilter_LNil]) 2); -by (etac Domain_findRelE 1); -(*case q x*) -by (case_tac "p x" 1); -by (asm_simp_tac (!simpset addsimps [findRel_imp_lfilter, - findRel_conj RS findRel_imp_lfilter]) 1); -by (Blast_tac 1); -(*case q x and ~(p x) *) -by (asm_simp_tac (!simpset addsimps [findRel_imp_lfilter]) 1); -by (case_tac "l' : Domain (findRel (%x. p x & q x))" 1); -(*subcase: there is no p&q in l' and therefore none in l*) -by (subgoal_tac "l ~: Domain (findRel (%x. p x & q x))" 2); -by (blast_tac (!claset addIs [findRel_not_conj_Domain]) 3); -by (subgoal_tac "lfilter q l' ~: Domain(findRel p)" 2); -by (blast_tac (!claset addIs [findRel_lfilter_Domain_conj]) 3); -(* ...and therefore too, no p in lfilter q l'. Both results are Lnil*) -by (asm_simp_tac (!simpset addsimps [diverge_lfilter_LNil]) 2); -(*subcase: there is a p&q in l' and therefore also one in l*) -by (etac Domain_findRelE 1); -by (subgoal_tac "(l, LCons xa l'a) : findRel(%x. p x & q x)" 1); -by (blast_tac (!claset addIs [findRel_conj2]) 2); -by (subgoal_tac "(lfilter q l', LCons xa (lfilter q l'a)) : findRel p" 1); -by (blast_tac (!claset addIs [findRel_conj_lfilter]) 2); -by (asm_simp_tac (!simpset addsimps [findRel_imp_lfilter]) 1); -by (Blast_tac 1); -val lemma = result(); - - -goal thy "lfilter p (lfilter q l) = lfilter (%x. p x & q x) l"; -by (res_inst_tac [("l","l")] llist_fun_equalityI 1); -by (ALLGOALS (simp_tac (!simpset setloop split_tac[expand_if]))); -by (blast_tac (!claset addIs [lemma, impOfSubs llistD_Fun_mono]) 1); -qed "lfilter_conj"; - - -(*** Numerous lemmas required to prove ??: - lfilter p (lmap f l) = lmap f (lfilter (%x. p(f x)) l) - ***) - -goal thy "!!p. (l,l') : findRel(%x. p (f x)) ==> lmap f l : Domain(findRel p)"; -by (etac findRel.induct 1); -by (ALLGOALS Asm_full_simp_tac); -qed "findRel_lmap_Domain"; - - -goal thy "!!p. lmap f l = LCons x l' --> \ -\ (EX y l''. x = f y & l' = lmap f l'' & l = LCons y l'')"; -by (stac (lmap_def RS def_llist_corec) 1); -by (res_inst_tac [("l", "l")] llistE 1); -by (Auto_tac()); -qed_spec_mp "lmap_eq_LCons"; - - -goal thy "!!p. (lx,ly) : findRel p ==> \ -\ ALL l. lmap f l = lx --> ly = LCons x l' --> \ -\ (EX y l''. x = f y & l' = lmap f l'' & \ -\ (l, LCons y l'') : findRel(%x. p(f x)))"; -by (etac findRel.induct 1); -by (ALLGOALS Asm_simp_tac); -by (safe_tac (!claset addSDs [lmap_eq_LCons])); -by (blast_tac (!claset addIs findRel.intrs) 1); -by (blast_tac (!claset addIs findRel.intrs) 1); -qed_spec_mp "lmap_LCons_findRel_lemma"; - -val lmap_LCons_findRel = refl RSN (2, refl RSN (2, lmap_LCons_findRel_lemma)); - -goal thy "lfilter p (lmap f l) = lmap f (lfilter (p o f) l)"; -by (res_inst_tac [("l","l")] llist_fun_equalityI 1); -by (ALLGOALS (simp_tac (!simpset setloop split_tac[expand_if]))); -by (Step_tac 1); -by (Blast_tac 1); -by (case_tac "lmap f l : Domain (findRel p)" 1); -by (subgoal_tac "l ~: Domain (findRel(%x. p (f x)))" 2); -by (blast_tac (!claset addIs [findRel_lmap_Domain]) 3); -by (asm_simp_tac (!simpset addsimps [diverge_lfilter_LNil]) 2); -by (etac Domain_findRelE 1); -by (forward_tac [lmap_LCons_findRel] 1); -by (Step_tac 1); -by (asm_simp_tac (!simpset addsimps [findRel_imp_lfilter]) 1); -by (Blast_tac 1); -qed "lfilter_lmap"; diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/LFilter.thy --- a/src/HOL/ex/LFilter.thy Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,29 +0,0 @@ -(* Title: HOL/LList.thy - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1997 University of Cambridge - -The "filter" functional for coinductive lists - --defined by a combination of induction and coinduction -*) - -LFilter = LList + Relation + - -consts - findRel :: "('a => bool) => ('a llist * 'a llist)set" - -inductive "findRel p" - intrs - found "p x ==> (LCons x l, LCons x l) : findRel p" - seek "[| ~p x; (l,l') : findRel p |] ==> (LCons x l, l') : findRel p" - -constdefs - find :: ['a => bool, 'a llist] => 'a llist - "find p l == @l'. (l,l'): findRel p | (l' = LNil & l ~: Domain(findRel p))" - - lfilter :: ['a => bool, 'a llist] => 'a llist - "lfilter p l == llist_corec l (%l. case find p l of - LNil => Inl () - | LCons y z => Inr(y,z))" - -end diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/LList.ML --- a/src/HOL/ex/LList.ML Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,886 +0,0 @@ -(* Title: HOL/ex/LList - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1993 University of Cambridge - -SHOULD LListD_Fun_CONS_I, etc., be equations (for rewriting)? -*) - -open LList; - -(** Simplification **) - -simpset := !simpset setloop split_tac [expand_split, expand_sum_case]; - -(*For adding _eqI rules to a simpset; we must remove Pair_eq because - it may turn an instance of reflexivity into a conjunction!*) -fun add_eqI ss = ss addsimps [range_eqI, image_eqI] - delsimps [Pair_eq]; - - -(*This justifies using llist in other recursive type definitions*) -goalw LList.thy llist.defs "!!A B. A<=B ==> llist(A) <= llist(B)"; -by (rtac gfp_mono 1); -by (REPEAT (ares_tac basic_monos 1)); -qed "llist_mono"; - - -goal LList.thy "llist(A) = {Numb(0)} <+> (A <*> llist(A))"; -let val rew = rewrite_rule [NIL_def, CONS_def] in -by (fast_tac (!claset addSIs (equalityI :: map rew llist.intrs) - addEs [rew llist.elim]) 1) -end; -qed "llist_unfold"; - - -(*** Type checking by coinduction, using list_Fun - THE COINDUCTIVE DEFINITION PACKAGE COULD DO THIS! -***) - -goalw LList.thy [list_Fun_def] - "!!M. [| M : X; X <= list_Fun A (X Un llist(A)) |] ==> M : llist(A)"; -by (etac llist.coinduct 1); -by (etac (subsetD RS CollectD) 1); -by (assume_tac 1); -qed "llist_coinduct"; - -goalw LList.thy [list_Fun_def, NIL_def] "NIL: list_Fun A X"; -by (Fast_tac 1); -qed "list_Fun_NIL_I"; - -goalw LList.thy [list_Fun_def,CONS_def] - "!!M N. [| M: A; N: X |] ==> CONS M N : list_Fun A X"; -by (Fast_tac 1); -qed "list_Fun_CONS_I"; - -(*Utilise the "strong" part, i.e. gfp(f)*) -goalw LList.thy (llist.defs @ [list_Fun_def]) - "!!M N. M: llist(A) ==> M : list_Fun A (X Un llist(A))"; -by (etac (llist.mono RS gfp_fun_UnI2) 1); -qed "list_Fun_llist_I"; - -(*** LList_corec satisfies the desired recurion equation ***) - -(*A continuity result?*) -goalw LList.thy [CONS_def] "CONS M (UN x.f(x)) = (UN x. CONS M (f x))"; -by (simp_tac (!simpset addsimps [In1_UN1, Scons_UN1_y]) 1); -qed "CONS_UN1"; - -(*UNUSED; obsolete? -goal Prod.thy "split p (%x y.UN z.f x y z) = (UN z. split p (%x y.f x y z))"; -by (simp_tac (!simpset setloop (split_tac [expand_split])) 1); -qed "split_UN1"; - -goal Sum.thy "sum_case s f (%y.UN z.g y z) = (UN z.sum_case s f (%y.g y z))"; -by (simp_tac (!simpset setloop (split_tac [expand_sum_case])) 1); -qed "sum_case2_UN1"; -*) - -val prems = goalw LList.thy [CONS_def] - "[| M<=M'; N<=N' |] ==> CONS M N <= CONS M' N'"; -by (REPEAT (resolve_tac ([In1_mono,Scons_mono]@prems) 1)); -qed "CONS_mono"; - -Addsimps [LList_corec_fun_def RS def_nat_rec_0, - LList_corec_fun_def RS def_nat_rec_Suc]; - -(** The directions of the equality are proved separately **) - -goalw LList.thy [LList_corec_def] - "LList_corec a f <= sum_case (%u.NIL) \ -\ (split(%z w. CONS z (LList_corec w f))) (f a)"; -by (rtac UN1_least 1); -by (res_inst_tac [("n","k")] natE 1); -by (ALLGOALS (Asm_simp_tac)); -by (REPEAT (resolve_tac [allI, impI, subset_refl RS CONS_mono, UN1_upper] 1)); -qed "LList_corec_subset1"; - -goalw LList.thy [LList_corec_def] - "sum_case (%u.NIL) (split(%z w. CONS z (LList_corec w f))) (f a) <= \ -\ LList_corec a f"; -by (simp_tac (!simpset addsimps [CONS_UN1]) 1); -by (safe_tac (!claset)); -by (ALLGOALS (res_inst_tac [("x","Suc(?k)")] UN1_I THEN' Asm_simp_tac)); -qed "LList_corec_subset2"; - -(*the recursion equation for LList_corec -- NOT SUITABLE FOR REWRITING!*) -goal LList.thy - "LList_corec a f = sum_case (%u. NIL) \ -\ (split(%z w. CONS z (LList_corec w f))) (f a)"; -by (REPEAT (resolve_tac [equalityI, LList_corec_subset1, - LList_corec_subset2] 1)); -qed "LList_corec"; - -(*definitional version of same*) -val [rew] = goal LList.thy - "[| !!x. h(x) == LList_corec x f |] ==> \ -\ h(a) = sum_case (%u.NIL) (split(%z w. CONS z (h w))) (f a)"; -by (rewtac rew); -by (rtac LList_corec 1); -qed "def_LList_corec"; - -(*A typical use of co-induction to show membership in the gfp. - Bisimulation is range(%x. LList_corec x f) *) -goal LList.thy "LList_corec a f : llist({u.True})"; -by (res_inst_tac [("X", "range(%x.LList_corec x ?g)")] llist_coinduct 1); -by (rtac rangeI 1); -by (safe_tac (!claset)); -by (stac LList_corec 1); -by (simp_tac (!simpset addsimps [list_Fun_NIL_I, list_Fun_CONS_I, CollectI] - |> add_eqI) 1); -qed "LList_corec_type"; - -(*Lemma for the proof of llist_corec*) -goal LList.thy - "LList_corec a (%z.sum_case Inl (split(%v w.Inr((Leaf(v),w)))) (f z)) : \ -\ llist(range Leaf)"; -by (res_inst_tac [("X", "range(%x.LList_corec x ?g)")] llist_coinduct 1); -by (rtac rangeI 1); -by (safe_tac (!claset)); -by (stac LList_corec 1); -by (asm_simp_tac (!simpset addsimps [list_Fun_NIL_I]) 1); -by (fast_tac (!claset addSIs [list_Fun_CONS_I]) 1); -qed "LList_corec_type2"; - - -(**** llist equality as a gfp; the bisimulation principle ****) - -(*This theorem is actually used, unlike the many similar ones in ZF*) -goal LList.thy "LListD(r) = diag({Numb(0)}) <++> (r <**> LListD(r))"; -let val rew = rewrite_rule [NIL_def, CONS_def] in -by (fast_tac (!claset addSIs (equalityI :: map rew LListD.intrs) - addEs [rew LListD.elim]) 1) -end; -qed "LListD_unfold"; - -goal LList.thy "!M N. (M,N) : LListD(diag(A)) --> ntrunc k M = ntrunc k N"; -by (res_inst_tac [("n", "k")] less_induct 1); -by (safe_tac ((claset_of "Fun") delrules [equalityI])); -by (etac LListD.elim 1); -by (safe_tac (((claset_of "Prod") delrules [equalityI]) addSEs [diagE])); -by (res_inst_tac [("n", "n")] natE 1); -by (asm_simp_tac (!simpset addsimps [ntrunc_0]) 1); -by (rename_tac "n'" 1); -by (res_inst_tac [("n", "n'")] natE 1); -by (asm_simp_tac (!simpset addsimps [CONS_def, ntrunc_one_In1]) 1); -by (asm_simp_tac (!simpset addsimps [CONS_def, ntrunc_In1, ntrunc_Scons, less_Suc_eq]) 1); -qed "LListD_implies_ntrunc_equality"; - -(*The domain of the LListD relation*) -goalw LList.thy (llist.defs @ [NIL_def, CONS_def]) - "fst``LListD(diag(A)) <= llist(A)"; -by (rtac gfp_upperbound 1); -(*avoids unfolding LListD on the rhs*) -by (res_inst_tac [("P", "%x. fst``x <= ?B")] (LListD_unfold RS ssubst) 1); -by (Simp_tac 1); -by (Fast_tac 1); -qed "fst_image_LListD"; - -(*This inclusion justifies the use of coinduction to show M=N*) -goal LList.thy "LListD(diag(A)) <= diag(llist(A))"; -by (rtac subsetI 1); -by (res_inst_tac [("p","x")] PairE 1); -by (safe_tac (!claset)); -by (rtac diag_eqI 1); -by (rtac (LListD_implies_ntrunc_equality RS spec RS spec RS mp RS - ntrunc_equality) 1); -by (assume_tac 1); -by (etac (fst_imageI RS (fst_image_LListD RS subsetD)) 1); -qed "LListD_subset_diag"; - - -(** Coinduction, using LListD_Fun - THE COINDUCTIVE DEFINITION PACKAGE COULD DO THIS! - **) - -goalw thy [LListD_Fun_def] "!!A B. A<=B ==> LListD_Fun r A <= LListD_Fun r B"; -by (REPEAT (ares_tac basic_monos 1)); -qed "LListD_Fun_mono"; - -goalw LList.thy [LListD_Fun_def] - "!!M. [| M : X; X <= LListD_Fun r (X Un LListD(r)) |] ==> M : LListD(r)"; -by (etac LListD.coinduct 1); -by (etac (subsetD RS CollectD) 1); -by (assume_tac 1); -qed "LListD_coinduct"; - -goalw LList.thy [LListD_Fun_def,NIL_def] "(NIL,NIL) : LListD_Fun r s"; -by (Fast_tac 1); -qed "LListD_Fun_NIL_I"; - -goalw LList.thy [LListD_Fun_def,CONS_def] - "!!x. [| x:A; (M,N):s |] ==> (CONS x M, CONS x N) : LListD_Fun (diag A) s"; -by (Fast_tac 1); -qed "LListD_Fun_CONS_I"; - -(*Utilise the "strong" part, i.e. gfp(f)*) -goalw LList.thy (LListD.defs @ [LListD_Fun_def]) - "!!M N. M: LListD(r) ==> M : LListD_Fun r (X Un LListD(r))"; -by (etac (LListD.mono RS gfp_fun_UnI2) 1); -qed "LListD_Fun_LListD_I"; - - -(*This converse inclusion helps to strengthen LList_equalityI*) -goal LList.thy "diag(llist(A)) <= LListD(diag(A))"; -by (rtac subsetI 1); -by (etac LListD_coinduct 1); -by (rtac subsetI 1); -by (etac diagE 1); -by (etac ssubst 1); -by (eresolve_tac [llist.elim] 1); -by (ALLGOALS - (asm_simp_tac (!simpset addsimps [diagI, LListD_Fun_NIL_I, - LListD_Fun_CONS_I]))); -qed "diag_subset_LListD"; - -goal LList.thy "LListD(diag(A)) = diag(llist(A))"; -by (REPEAT (resolve_tac [equalityI, LListD_subset_diag, - diag_subset_LListD] 1)); -qed "LListD_eq_diag"; - -goal LList.thy - "!!M N. M: llist(A) ==> (M,M) : LListD_Fun (diag A) (X Un diag(llist(A)))"; -by (rtac (LListD_eq_diag RS subst) 1); -by (rtac LListD_Fun_LListD_I 1); -by (asm_simp_tac (!simpset addsimps [LListD_eq_diag, diagI]) 1); -qed "LListD_Fun_diag_I"; - - -(** To show two LLists are equal, exhibit a bisimulation! - [also admits true equality] - Replace "A" by some particular set, like {x.True}??? *) -goal LList.thy - "!!r. [| (M,N) : r; r <= LListD_Fun (diag A) (r Un diag(llist(A))) \ -\ |] ==> M=N"; -by (rtac (LListD_subset_diag RS subsetD RS diagE) 1); -by (etac LListD_coinduct 1); -by (asm_simp_tac (!simpset addsimps [LListD_eq_diag]) 1); -by (safe_tac (!claset)); -qed "LList_equalityI"; - - -(*** Finality of llist(A): Uniqueness of functions defined by corecursion ***) - -(*abstract proof using a bisimulation*) -val [prem1,prem2] = goal LList.thy - "[| !!x. h1(x) = sum_case (%u.NIL) (split(%z w. CONS z (h1 w))) (f x); \ -\ !!x. h2(x) = sum_case (%u.NIL) (split(%z w. CONS z (h2 w))) (f x) |]\ -\ ==> h1=h2"; -by (rtac ext 1); -(*next step avoids an unknown (and flexflex pair) in simplification*) -by (res_inst_tac [("A", "{u.True}"), - ("r", "range(%u. (h1(u),h2(u)))")] LList_equalityI 1); -by (rtac rangeI 1); -by (safe_tac (!claset)); -by (stac prem1 1); -by (stac prem2 1); -by (simp_tac (!simpset addsimps [LListD_Fun_NIL_I, - CollectI RS LListD_Fun_CONS_I] - |> add_eqI) 1); -qed "LList_corec_unique"; - -val [prem] = goal LList.thy - "[| !!x. h(x) = sum_case (%u.NIL) (split(%z w. CONS z (h w))) (f x) |] \ -\ ==> h = (%x.LList_corec x f)"; -by (rtac (LList_corec RS (prem RS LList_corec_unique)) 1); -qed "equals_LList_corec"; - - -(** Obsolete LList_corec_unique proof: complete induction, not coinduction **) - -goalw LList.thy [CONS_def] "ntrunc (Suc 0) (CONS M N) = {}"; -by (rtac ntrunc_one_In1 1); -qed "ntrunc_one_CONS"; - -goalw LList.thy [CONS_def] - "ntrunc (Suc(Suc(k))) (CONS M N) = CONS (ntrunc k M) (ntrunc k N)"; -by (simp_tac (!simpset addsimps [ntrunc_Scons,ntrunc_In1]) 1); -qed "ntrunc_CONS"; - -val [prem1,prem2] = goal LList.thy - "[| !!x. h1(x) = sum_case (%u.NIL) (split(%z w. CONS z (h1 w))) (f x); \ -\ !!x. h2(x) = sum_case (%u.NIL) (split(%z w. CONS z (h2 w))) (f x) |]\ -\ ==> h1=h2"; -by (rtac (ntrunc_equality RS ext) 1); -by (rename_tac "x k" 1); -by (res_inst_tac [("x", "x")] spec 1); -by (res_inst_tac [("n", "k")] less_induct 1); -by (rename_tac "n" 1); -by (rtac allI 1); -by (rename_tac "y" 1); -by (stac prem1 1); -by (stac prem2 1); -by (simp_tac (!simpset setloop (split_tac [expand_sum_case])) 1); -by (strip_tac 1); -by (res_inst_tac [("n", "n")] natE 1); -by (rename_tac "m" 2); -by (res_inst_tac [("n", "m")] natE 2); -by (ALLGOALS(asm_simp_tac(!simpset addsimps - [ntrunc_0,ntrunc_one_CONS,ntrunc_CONS, less_Suc_eq]))); -result(); - - -(*** Lconst -- defined directly using lfp, but equivalent to a LList_corec ***) - -goal LList.thy "mono(CONS(M))"; -by (REPEAT (ares_tac [monoI, subset_refl, CONS_mono] 1)); -qed "Lconst_fun_mono"; - -(* Lconst(M) = CONS M (Lconst M) *) -bind_thm ("Lconst", (Lconst_fun_mono RS (Lconst_def RS def_lfp_Tarski))); - -(*A typical use of co-induction to show membership in the gfp. - The containing set is simply the singleton {Lconst(M)}. *) -goal LList.thy "!!M A. M:A ==> Lconst(M): llist(A)"; -by (rtac (singletonI RS llist_coinduct) 1); -by (safe_tac (!claset)); -by (res_inst_tac [("P", "%u. u: ?A")] (Lconst RS ssubst) 1); -by (REPEAT (ares_tac [list_Fun_CONS_I, singletonI, UnI1] 1)); -qed "Lconst_type"; - -goal LList.thy "Lconst(M) = LList_corec M (%x.Inr((x,x)))"; -by (rtac (equals_LList_corec RS fun_cong) 1); -by (Simp_tac 1); -by (rtac Lconst 1); -qed "Lconst_eq_LList_corec"; - -(*Thus we could have used gfp in the definition of Lconst*) -goal LList.thy "gfp(%N. CONS M N) = LList_corec M (%x.Inr((x,x)))"; -by (rtac (equals_LList_corec RS fun_cong) 1); -by (Simp_tac 1); -by (rtac (Lconst_fun_mono RS gfp_Tarski) 1); -qed "gfp_Lconst_eq_LList_corec"; - - -(*** Isomorphisms ***) - -goal LList.thy "inj(Rep_llist)"; -by (rtac inj_inverseI 1); -by (rtac Rep_llist_inverse 1); -qed "inj_Rep_llist"; - -goal LList.thy "inj_onto Abs_llist (llist(range Leaf))"; -by (rtac inj_onto_inverseI 1); -by (etac Abs_llist_inverse 1); -qed "inj_onto_Abs_llist"; - -(** Distinctness of constructors **) - -goalw LList.thy [LNil_def,LCons_def] "~ LCons x xs = LNil"; -by (rtac (CONS_not_NIL RS (inj_onto_Abs_llist RS inj_onto_contraD)) 1); -by (REPEAT (resolve_tac (llist.intrs @ [rangeI, Rep_llist]) 1)); -qed "LCons_not_LNil"; - -bind_thm ("LNil_not_LCons", LCons_not_LNil RS not_sym); - -AddIffs [LCons_not_LNil, LNil_not_LCons]; - - -(** llist constructors **) - -goalw LList.thy [LNil_def] - "Rep_llist(LNil) = NIL"; -by (rtac (llist.NIL_I RS Abs_llist_inverse) 1); -qed "Rep_llist_LNil"; - -goalw LList.thy [LCons_def] - "Rep_llist(LCons x l) = CONS (Leaf x) (Rep_llist l)"; -by (REPEAT (resolve_tac [llist.CONS_I RS Abs_llist_inverse, - rangeI, Rep_llist] 1)); -qed "Rep_llist_LCons"; - -(** Injectiveness of CONS and LCons **) - -goalw LList.thy [CONS_def] "(CONS M N=CONS M' N') = (M=M' & N=N')"; -by (fast_tac (!claset addSEs [Scons_inject, make_elim In1_inject]) 1); -qed "CONS_CONS_eq2"; - -bind_thm ("CONS_inject", (CONS_CONS_eq RS iffD1 RS conjE)); - - -(*For reasoning about abstract llist constructors*) - -AddIs ([Rep_llist]@llist.intrs); -AddSDs [inj_onto_Abs_llist RS inj_ontoD, - inj_Rep_llist RS injD, Leaf_inject]; - -goalw LList.thy [LCons_def] "(LCons x xs=LCons y ys) = (x=y & xs=ys)"; -by (Fast_tac 1); -qed "LCons_LCons_eq"; - -AddIffs [LCons_LCons_eq]; - -val [major] = goal LList.thy "CONS M N: llist(A) ==> M: A & N: llist(A)"; -by (rtac (major RS llist.elim) 1); -by (etac CONS_neq_NIL 1); -by (Fast_tac 1); -qed "CONS_D2"; - - -(****** Reasoning about llist(A) ******) - -Addsimps [List_case_NIL, List_case_CONS]; - -(*A special case of list_equality for functions over lazy lists*) -val [Mlist,gMlist,NILcase,CONScase] = goal LList.thy - "[| M: llist(A); g(NIL): llist(A); \ -\ f(NIL)=g(NIL); \ -\ !!x l. [| x:A; l: llist(A) |] ==> \ -\ (f(CONS x l),g(CONS x l)) : \ -\ LListD_Fun (diag A) ((%u.(f(u),g(u)))``llist(A) Un \ -\ diag(llist(A))) \ -\ |] ==> f(M) = g(M)"; -by (rtac LList_equalityI 1); -by (rtac (Mlist RS imageI) 1); -by (rtac subsetI 1); -by (etac imageE 1); -by (etac ssubst 1); -by (etac llist.elim 1); -by (etac ssubst 1); -by (stac NILcase 1); -by (rtac (gMlist RS LListD_Fun_diag_I) 1); -by (etac ssubst 1); -by (REPEAT (ares_tac [CONScase] 1)); -qed "LList_fun_equalityI"; - - -(*** The functional "Lmap" ***) - -goal LList.thy "Lmap f NIL = NIL"; -by (rtac (Lmap_def RS def_LList_corec RS trans) 1); -by (Simp_tac 1); -qed "Lmap_NIL"; - -goal LList.thy "Lmap f (CONS M N) = CONS (f M) (Lmap f N)"; -by (rtac (Lmap_def RS def_LList_corec RS trans) 1); -by (Simp_tac 1); -qed "Lmap_CONS"; - -(*Another type-checking proof by coinduction*) -val [major,minor] = goal LList.thy - "[| M: llist(A); !!x. x:A ==> f(x):B |] ==> Lmap f M: llist(B)"; -by (rtac (major RS imageI RS llist_coinduct) 1); -by (safe_tac (!claset)); -by (etac llist.elim 1); -by (ALLGOALS (asm_simp_tac (!simpset addsimps [Lmap_NIL,Lmap_CONS]))); -by (REPEAT (ares_tac [list_Fun_NIL_I, list_Fun_CONS_I, - minor, imageI, UnI1] 1)); -qed "Lmap_type"; - -(*This type checking rule synthesises a sufficiently large set for f*) -val [major] = goal LList.thy "M: llist(A) ==> Lmap f M: llist(f``A)"; -by (rtac (major RS Lmap_type) 1); -by (etac imageI 1); -qed "Lmap_type2"; - -(** Two easy results about Lmap **) - -val [prem] = goalw LList.thy [o_def] - "M: llist(A) ==> Lmap (f o g) M = Lmap f (Lmap g M)"; -by (rtac (prem RS imageI RS LList_equalityI) 1); -by (safe_tac (!claset)); -by (etac llist.elim 1); -by (ALLGOALS (asm_simp_tac (!simpset addsimps [Lmap_NIL,Lmap_CONS]))); -by (REPEAT (ares_tac [LListD_Fun_NIL_I, imageI, UnI1, - rangeI RS LListD_Fun_CONS_I] 1)); -qed "Lmap_compose"; - -val [prem] = goal LList.thy "M: llist(A) ==> Lmap (%x.x) M = M"; -by (rtac (prem RS imageI RS LList_equalityI) 1); -by (safe_tac (!claset)); -by (etac llist.elim 1); -by (ALLGOALS (asm_simp_tac (!simpset addsimps [Lmap_NIL,Lmap_CONS]))); -by (REPEAT (ares_tac [LListD_Fun_NIL_I, imageI RS UnI1, - rangeI RS LListD_Fun_CONS_I] 1)); -qed "Lmap_ident"; - - -(*** Lappend -- its two arguments cause some complications! ***) - -goalw LList.thy [Lappend_def] "Lappend NIL NIL = NIL"; -by (rtac (LList_corec RS trans) 1); -by (Simp_tac 1); -qed "Lappend_NIL_NIL"; - -goalw LList.thy [Lappend_def] - "Lappend NIL (CONS N N') = CONS N (Lappend NIL N')"; -by (rtac (LList_corec RS trans) 1); -by (Simp_tac 1); -qed "Lappend_NIL_CONS"; - -goalw LList.thy [Lappend_def] - "Lappend (CONS M M') N = CONS M (Lappend M' N)"; -by (rtac (LList_corec RS trans) 1); -by (Simp_tac 1); -qed "Lappend_CONS"; - -Addsimps [llist.NIL_I, Lappend_NIL_NIL, Lappend_NIL_CONS, - Lappend_CONS, LListD_Fun_CONS_I, range_eqI, image_eqI]; -Delsimps [Pair_eq]; - -goal LList.thy "!!M. M: llist(A) ==> Lappend NIL M = M"; -by (etac LList_fun_equalityI 1); -by (ALLGOALS Asm_simp_tac); -qed "Lappend_NIL"; - -goal LList.thy "!!M. M: llist(A) ==> Lappend M NIL = M"; -by (etac LList_fun_equalityI 1); -by (ALLGOALS Asm_simp_tac); -qed "Lappend_NIL2"; - -(** Alternative type-checking proofs for Lappend **) - -(*weak co-induction: bisimulation and case analysis on both variables*) -goal LList.thy - "!!M N. [| M: llist(A); N: llist(A) |] ==> Lappend M N: llist(A)"; -by (res_inst_tac - [("X", "UN u:llist(A). UN v: llist(A). {Lappend u v}")] llist_coinduct 1); -by (Fast_tac 1); -by (safe_tac (!claset)); -by (eres_inst_tac [("a", "u")] llist.elim 1); -by (eres_inst_tac [("a", "v")] llist.elim 1); -by (ALLGOALS - (Asm_simp_tac THEN' - fast_tac (!claset addSIs [llist.NIL_I, list_Fun_NIL_I, list_Fun_CONS_I]))); -qed "Lappend_type"; - -(*strong co-induction: bisimulation and case analysis on one variable*) -goal LList.thy - "!!M N. [| M: llist(A); N: llist(A) |] ==> Lappend M N: llist(A)"; -by (res_inst_tac [("X", "(%u.Lappend u N)``llist(A)")] llist_coinduct 1); -by (etac imageI 1); -by (rtac subsetI 1); -by (etac imageE 1); -by (eres_inst_tac [("a", "u")] llist.elim 1); -by (asm_simp_tac (!simpset addsimps [Lappend_NIL, list_Fun_llist_I]) 1); -by (Asm_simp_tac 1); -by (fast_tac (!claset addSIs [list_Fun_CONS_I]) 1); -qed "Lappend_type"; - -(**** Lazy lists as the type 'a llist -- strongly typed versions of above ****) - -(** llist_case: case analysis for 'a llist **) - -Addsimps ([Abs_llist_inverse, Rep_llist_inverse, - Rep_llist, rangeI, inj_Leaf, inv_f_f] @ llist.intrs); - -goalw LList.thy [llist_case_def,LNil_def] "llist_case c d LNil = c"; -by (Simp_tac 1); -qed "llist_case_LNil"; - -goalw LList.thy [llist_case_def,LCons_def] - "llist_case c d (LCons M N) = d M N"; -by (Simp_tac 1); -qed "llist_case_LCons"; - -(*Elimination is case analysis, not induction.*) -val [prem1,prem2] = goalw LList.thy [NIL_def,CONS_def] - "[| l=LNil ==> P; !!x l'. l=LCons x l' ==> P \ -\ |] ==> P"; -by (rtac (Rep_llist RS llist.elim) 1); -by (rtac (inj_Rep_llist RS injD RS prem1) 1); -by (stac Rep_llist_LNil 1); -by (assume_tac 1); -by (etac rangeE 1); -by (rtac (inj_Rep_llist RS injD RS prem2) 1); -by (asm_simp_tac (!simpset delsimps [CONS_CONS_eq] addsimps [Rep_llist_LCons]) 1); -by (etac (Abs_llist_inverse RS ssubst) 1); -by (rtac refl 1); -qed "llistE"; - -(** llist_corec: corecursion for 'a llist **) - -goalw LList.thy [llist_corec_def,LNil_def,LCons_def] - "llist_corec a f = sum_case (%u. LNil) \ -\ (split(%z w. LCons z (llist_corec w f))) (f a)"; -by (stac LList_corec 1); -by (res_inst_tac [("s","f(a)")] sumE 1); -by (asm_simp_tac (!simpset addsimps [LList_corec_type2]) 1); -by (res_inst_tac [("p","y")] PairE 1); -by (asm_simp_tac (!simpset addsimps [LList_corec_type2]) 1); -(*FIXME: correct case splits usd to be found automatically: -by (ASM_SIMP_TAC(!simpset addsimps [LList_corec_type2]) 1);*) -qed "llist_corec"; - -(*definitional version of same*) -val [rew] = goal LList.thy - "[| !!x. h(x) == llist_corec x f |] ==> \ -\ h(a) = sum_case (%u.LNil) (split(%z w. LCons z (h w))) (f a)"; -by (rewtac rew); -by (rtac llist_corec 1); -qed "def_llist_corec"; - -(**** Proofs about type 'a llist functions ****) - -(*** Deriving llist_equalityI -- llist equality is a bisimulation ***) - -goalw LList.thy [LListD_Fun_def] - "!!r A. r <= (llist A) Times (llist A) ==> \ -\ LListD_Fun (diag A) r <= (llist A) Times (llist A)"; -by (stac llist_unfold 1); -by (simp_tac (!simpset addsimps [NIL_def, CONS_def]) 1); -by (Fast_tac 1); -qed "LListD_Fun_subset_Sigma_llist"; - -goal LList.thy - "prod_fun Rep_llist Rep_llist `` r <= \ -\ (llist(range Leaf)) Times (llist(range Leaf))"; -by (fast_tac (!claset addIs [Rep_llist]) 1); -qed "subset_Sigma_llist"; - -val [prem] = goal LList.thy - "r <= (llist(range Leaf)) Times (llist(range Leaf)) ==> \ -\ prod_fun (Rep_llist o Abs_llist) (Rep_llist o Abs_llist) `` r <= r"; -by (safe_tac (!claset)); -by (rtac (prem RS subsetD RS SigmaE2) 1); -by (assume_tac 1); -by (asm_simp_tac (!simpset addsimps [o_def,prod_fun,Abs_llist_inverse]) 1); -qed "prod_fun_lemma"; - -goal LList.thy - "prod_fun Rep_llist Rep_llist `` range(%x. (x, x)) = \ -\ diag(llist(range Leaf))"; -by (rtac equalityI 1); -by (fast_tac (!claset addIs [Rep_llist]) 1); -by (fast_tac (!claset addSEs [Abs_llist_inverse RS subst]) 1); -qed "prod_fun_range_eq_diag"; - -(*Surprisingly hard to prove. Used with lfilter*) -goalw thy [llistD_Fun_def, prod_fun_def] - "!!A B. A<=B ==> llistD_Fun A <= llistD_Fun B"; -by (Auto_tac()); -by (rtac image_eqI 1); -by (fast_tac (!claset addss (!simpset)) 1); -by (blast_tac (!claset addIs [impOfSubs LListD_Fun_mono]) 1); -qed "llistD_Fun_mono"; - -(** To show two llists are equal, exhibit a bisimulation! - [also admits true equality] **) -val [prem1,prem2] = goalw LList.thy [llistD_Fun_def] - "[| (l1,l2) : r; r <= llistD_Fun(r Un range(%x.(x,x))) |] ==> l1=l2"; -by (rtac (inj_Rep_llist RS injD) 1); -by (res_inst_tac [("r", "prod_fun Rep_llist Rep_llist ``r"), - ("A", "range(Leaf)")] - LList_equalityI 1); -by (rtac (prem1 RS prod_fun_imageI) 1); -by (rtac (prem2 RS image_mono RS subset_trans) 1); -by (rtac (image_compose RS subst) 1); -by (rtac (prod_fun_compose RS subst) 1); -by (stac image_Un 1); -by (stac prod_fun_range_eq_diag 1); -by (rtac (LListD_Fun_subset_Sigma_llist RS prod_fun_lemma) 1); -by (rtac (subset_Sigma_llist RS Un_least) 1); -by (rtac diag_subset_Sigma 1); -qed "llist_equalityI"; - -(** Rules to prove the 2nd premise of llist_equalityI **) -goalw LList.thy [llistD_Fun_def,LNil_def] "(LNil,LNil) : llistD_Fun(r)"; -by (rtac (LListD_Fun_NIL_I RS prod_fun_imageI) 1); -qed "llistD_Fun_LNil_I"; - -val [prem] = goalw LList.thy [llistD_Fun_def,LCons_def] - "(l1,l2):r ==> (LCons x l1, LCons x l2) : llistD_Fun(r)"; -by (rtac (rangeI RS LListD_Fun_CONS_I RS prod_fun_imageI) 1); -by (rtac (prem RS prod_fun_imageI) 1); -qed "llistD_Fun_LCons_I"; - -(*Utilise the "strong" part, i.e. gfp(f)*) -goalw LList.thy [llistD_Fun_def] - "!!l. (l,l) : llistD_Fun(r Un range(%x.(x,x)))"; -by (rtac (Rep_llist_inverse RS subst) 1); -by (rtac prod_fun_imageI 1); -by (stac image_Un 1); -by (stac prod_fun_range_eq_diag 1); -by (rtac (Rep_llist RS LListD_Fun_diag_I) 1); -qed "llistD_Fun_range_I"; - -(*A special case of list_equality for functions over lazy lists*) -val [prem1,prem2] = goal LList.thy - "[| f(LNil)=g(LNil); \ -\ !!x l. (f(LCons x l),g(LCons x l)) : \ -\ llistD_Fun(range(%u. (f(u),g(u))) Un range(%v. (v,v))) \ -\ |] ==> f(l) = (g(l :: 'a llist) :: 'b llist)"; -by (res_inst_tac [("r", "range(%u. (f(u),g(u)))")] llist_equalityI 1); -by (rtac rangeI 1); -by (rtac subsetI 1); -by (etac rangeE 1); -by (etac ssubst 1); -by (res_inst_tac [("l", "u")] llistE 1); -by (etac ssubst 1); -by (stac prem1 1); -by (rtac llistD_Fun_range_I 1); -by (etac ssubst 1); -by (rtac prem2 1); -qed "llist_fun_equalityI"; - -(*simpset for llist bisimulations*) -Addsimps [llist_case_LNil, llist_case_LCons, - llistD_Fun_LNil_I, llistD_Fun_LCons_I]; - - -(*** The functional "lmap" ***) - -goal LList.thy "lmap f LNil = LNil"; -by (rtac (lmap_def RS def_llist_corec RS trans) 1); -by (Simp_tac 1); -qed "lmap_LNil"; - -goal LList.thy "lmap f (LCons M N) = LCons (f M) (lmap f N)"; -by (rtac (lmap_def RS def_llist_corec RS trans) 1); -by (Simp_tac 1); -qed "lmap_LCons"; - -Addsimps [lmap_LNil, lmap_LCons]; - - -(** Two easy results about lmap **) - -goal LList.thy "lmap (f o g) l = lmap f (lmap g l)"; -by (res_inst_tac [("l","l")] llist_fun_equalityI 1); -by (ALLGOALS Simp_tac); -qed "lmap_compose"; - -goal LList.thy "lmap (%x.x) l = l"; -by (res_inst_tac [("l","l")] llist_fun_equalityI 1); -by (ALLGOALS Simp_tac); -qed "lmap_ident"; - - -(*** iterates -- llist_fun_equalityI cannot be used! ***) - -goal LList.thy "iterates f x = LCons x (iterates f (f x))"; -by (rtac (iterates_def RS def_llist_corec RS trans) 1); -by (Simp_tac 1); -qed "iterates"; - -goal LList.thy "lmap f (iterates f x) = iterates f (f x)"; -by (res_inst_tac [("r", "range(%u.(lmap f (iterates f u),iterates f (f u)))")] - llist_equalityI 1); -by (rtac rangeI 1); -by (safe_tac (!claset)); -by (res_inst_tac [("x1", "f(u)")] (iterates RS ssubst) 1); -by (res_inst_tac [("x1", "u")] (iterates RS ssubst) 1); -by (Simp_tac 1); -qed "lmap_iterates"; - -goal LList.thy "iterates f x = LCons x (lmap f (iterates f x))"; -by (stac lmap_iterates 1); -by (rtac iterates 1); -qed "iterates_lmap"; - -(*** A rather complex proof about iterates -- cf Andy Pitts ***) - -(** Two lemmas about natrec n x (%m.g), which is essentially (g^n)(x) **) - -goal LList.thy - "nat_rec (LCons b l) (%m. lmap(f)) n = \ -\ LCons (nat_rec b (%m. f) n) (nat_rec l (%m. lmap(f)) n)"; -by (nat_ind_tac "n" 1); -by (ALLGOALS Asm_simp_tac); -qed "fun_power_lmap"; - -goal Nat.thy "nat_rec (g x) (%m. g) n = nat_rec x (%m. g) (Suc n)"; -by (nat_ind_tac "n" 1); -by (ALLGOALS Asm_simp_tac); -qed "fun_power_Suc"; - -val Pair_cong = read_instantiate_sg (sign_of Prod.thy) - [("f","Pair")] (standard(refl RS cong RS cong)); - -(*The bisimulation consists of {(lmap(f)^n (h(u)), lmap(f)^n (iterates(f,u)))} - for all u and all n::nat.*) -val [prem] = goal LList.thy - "(!!x. h(x) = LCons x (lmap f (h x))) ==> h = iterates(f)"; -by (rtac ext 1); -by (res_inst_tac [("r", - "UN u. range(%n. (nat_rec (h u) (%m y.lmap f y) n, \ -\ nat_rec (iterates f u) (%m y.lmap f y) n))")] - llist_equalityI 1); -by (REPEAT (resolve_tac [UN1_I, range_eqI, Pair_cong, nat_rec_0 RS sym] 1)); -by (safe_tac (!claset)); -by (stac iterates 1); -by (stac prem 1); -by (stac fun_power_lmap 1); -by (stac fun_power_lmap 1); -by (rtac llistD_Fun_LCons_I 1); -by (rtac (lmap_iterates RS subst) 1); -by (stac fun_power_Suc 1); -by (stac fun_power_Suc 1); -by (rtac (UN1_I RS UnI1) 1); -by (rtac rangeI 1); -qed "iterates_equality"; - - -(*** lappend -- its two arguments cause some complications! ***) - -goalw LList.thy [lappend_def] "lappend LNil LNil = LNil"; -by (rtac (llist_corec RS trans) 1); -by (Simp_tac 1); -qed "lappend_LNil_LNil"; - -goalw LList.thy [lappend_def] - "lappend LNil (LCons l l') = LCons l (lappend LNil l')"; -by (rtac (llist_corec RS trans) 1); -by (Simp_tac 1); -qed "lappend_LNil_LCons"; - -goalw LList.thy [lappend_def] - "lappend (LCons l l') N = LCons l (lappend l' N)"; -by (rtac (llist_corec RS trans) 1); -by (Simp_tac 1); -qed "lappend_LCons"; - -Addsimps [lappend_LNil_LNil, lappend_LNil_LCons, lappend_LCons]; - -goal LList.thy "lappend LNil l = l"; -by (res_inst_tac [("l","l")] llist_fun_equalityI 1); -by (ALLGOALS Simp_tac); -qed "lappend_LNil"; - -goal LList.thy "lappend l LNil = l"; -by (res_inst_tac [("l","l")] llist_fun_equalityI 1); -by (ALLGOALS Simp_tac); -qed "lappend_LNil2"; - -Addsimps [lappend_LNil, lappend_LNil2]; - -(*The infinite first argument blocks the second*) -goal LList.thy "lappend (iterates f x) N = iterates f x"; -by (res_inst_tac [("r", "range(%u.(lappend (iterates f u) N,iterates f u))")] - llist_equalityI 1); -by (rtac rangeI 1); -by (safe_tac (!claset)); -by (stac iterates 1); -by (Simp_tac 1); -qed "lappend_iterates"; - -(** Two proofs that lmap distributes over lappend **) - -(*Long proof requiring case analysis on both both arguments*) -goal LList.thy "lmap f (lappend l n) = lappend (lmap f l) (lmap f n)"; -by (res_inst_tac - [("r", - "UN n. range(%l.(lmap f (lappend l n),lappend (lmap f l) (lmap f n)))")] - llist_equalityI 1); -by (rtac UN1_I 1); -by (rtac rangeI 1); -by (safe_tac (!claset)); -by (res_inst_tac [("l", "l")] llistE 1); -by (res_inst_tac [("l", "n")] llistE 1); -by (ALLGOALS Asm_simp_tac); -by (REPEAT_SOME (ares_tac [llistD_Fun_LCons_I, UN1_I RS UnI1, rangeI])); -qed "lmap_lappend_distrib"; - -(*Shorter proof of theorem above using llist_equalityI as strong coinduction*) -goal LList.thy "lmap f (lappend l n) = lappend (lmap f l) (lmap f n)"; -by (res_inst_tac [("l","l")] llist_fun_equalityI 1); -by (Simp_tac 1); -by (Simp_tac 1); -qed "lmap_lappend_distrib"; - -(*Without strong coinduction, three case analyses might be needed*) -goal LList.thy "lappend (lappend l1 l2) l3 = lappend l1 (lappend l2 l3)"; -by (res_inst_tac [("l","l1")] llist_fun_equalityI 1); -by (Simp_tac 1); -by (Simp_tac 1); -qed "lappend_assoc"; diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/LList.thy --- a/src/HOL/ex/LList.thy Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,153 +0,0 @@ -(* Title: HOL/LList.thy - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1994 University of Cambridge - -Definition of type 'a llist by a greatest fixed point - -Shares NIL, CONS, List_case with List.thy - -Still needs filter and flatten functions -- hard because they need -bounds on the amount of lookahead required. - -Could try (but would it work for the gfp analogue of term?) - LListD_Fun_def "LListD_Fun(A) == (%Z.diag({Numb(0)}) <++> diag(A) <**> Z)" - -A nice but complex example would be [ML for the Working Programmer, page 176] - from(1) = enumerate (Lmap (Lmap(pack), makeqq(from(1),from(1)))) - -Previous definition of llistD_Fun was explicit: - llistD_Fun_def - "llistD_Fun(r) == - {(LNil,LNil)} Un - (UN x. (split(%l1 l2.(LCons(x,l1),LCons(x,l2))))``r)" -*) - -LList = Gfp + SList + - -types - 'a llist - -arities - llist :: (term)term - -consts - list_Fun :: ['a item set, 'a item set] => 'a item set - LListD_Fun :: - "[('a item * 'a item)set, ('a item * 'a item)set] => - ('a item * 'a item)set" - - llist :: 'a item set => 'a item set - LListD :: "('a item * 'a item)set => ('a item * 'a item)set" - llistD_Fun :: "('a llist * 'a llist)set => ('a llist * 'a llist)set" - - Rep_llist :: 'a llist => 'a item - Abs_llist :: 'a item => 'a llist - LNil :: 'a llist - LCons :: ['a, 'a llist] => 'a llist - - llist_case :: ['b, ['a, 'a llist]=>'b, 'a llist] => 'b - - LList_corec_fun :: "[nat, 'a=>unit+('b item * 'a), 'a] => 'b item" - LList_corec :: "['a, 'a => unit + ('b item * 'a)] => 'b item" - llist_corec :: "['a, 'a => unit + ('b * 'a)] => 'b llist" - - Lmap :: ('a item => 'b item) => ('a item => 'b item) - lmap :: ('a=>'b) => ('a llist => 'b llist) - - iterates :: ['a => 'a, 'a] => 'a llist - - Lconst :: 'a item => 'a item - Lappend :: ['a item, 'a item] => 'a item - lappend :: ['a llist, 'a llist] => 'a llist - - -coinductive "llist(A)" - intrs - NIL_I "NIL: llist(A)" - CONS_I "[| a: A; M: llist(A) |] ==> CONS a M : llist(A)" - -coinductive "LListD(r)" - intrs - NIL_I "(NIL, NIL) : LListD(r)" - CONS_I "[| (a,b): r; (M,N) : LListD(r) - |] ==> (CONS a M, CONS b N) : LListD(r)" - -translations - "case p of LNil => a | LCons x l => b" == "llist_case a (%x l.b) p" - - -defs - (*Now used exclusively for abbreviating the coinduction rule*) - list_Fun_def "list_Fun A X == - {z. z = NIL | (? M a. z = CONS a M & a : A & M : X)}" - - LListD_Fun_def "LListD_Fun r X == - {z. z = (NIL, NIL) | - (? M N a b. z = (CONS a M, CONS b N) & - (a, b) : r & (M, N) : X)}" - - (*defining the abstract constructors*) - LNil_def "LNil == Abs_llist(NIL)" - LCons_def "LCons x xs == Abs_llist(CONS (Leaf x) (Rep_llist xs))" - - llist_case_def - "llist_case c d l == - List_case c (%x y. d (inv Leaf x) (Abs_llist y)) (Rep_llist l)" - - LList_corec_fun_def - "LList_corec_fun k f == - nat_rec (%x. {}) - (%j r x. case f x of Inl u => NIL - | Inr(z,w) => CONS z (r w)) - k" - - LList_corec_def - "LList_corec a f == UN k. LList_corec_fun k f a" - - llist_corec_def - "llist_corec a f == - Abs_llist(LList_corec a - (%z.case f z of Inl x => Inl(x) - | Inr(v,w) => Inr(Leaf(v), w)))" - - llistD_Fun_def - "llistD_Fun(r) == - prod_fun Abs_llist Abs_llist `` - LListD_Fun (diag(range Leaf)) - (prod_fun Rep_llist Rep_llist `` r)" - - Lconst_def "Lconst(M) == lfp(%N. CONS M N)" - - Lmap_def - "Lmap f M == LList_corec M (List_case (Inl ()) (%x M'. Inr((f(x), M'))))" - - lmap_def - "lmap f l == llist_corec l (%z. case z of LNil => (Inl ()) - | LCons y z => Inr(f(y), z))" - - iterates_def "iterates f a == llist_corec a (%x. Inr((x, f(x))))" - -(*Append generates its result by applying f, where - f((NIL,NIL)) = Inl(()) - f((NIL, CONS N1 N2)) = Inr((N1, (NIL,N2)) - f((CONS M1 M2, N)) = Inr((M1, (M2,N)) -*) - - Lappend_def - "Lappend M N == LList_corec (M,N) - (split(List_case (List_case (Inl ()) (%N1 N2. Inr((N1, (NIL,N2))))) - (%M1 M2 N. Inr((M1, (M2,N))))))" - - lappend_def - "lappend l n == llist_corec (l,n) - (split(llist_case (llist_case (Inl ()) (%n1 n2. Inr((n1, (LNil,n2))))) - (%l1 l2 n. Inr((l1, (l2,n))))))" - -rules - (*faking a type definition...*) - Rep_llist "Rep_llist(xs): llist(range(Leaf))" - Rep_llist_inverse "Abs_llist(Rep_llist(xs)) = xs" - Abs_llist_inverse "M: llist(range(Leaf)) ==> Rep_llist(Abs_llist(M)) = M" - -end diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/Mutil.ML --- a/src/HOL/ex/Mutil.ML Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,172 +0,0 @@ -(* Title: HOL/ex/Mutil - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1996 University of Cambridge - -The Mutilated Chess Board Problem, formalized inductively -*) - -open Mutil; - -Addsimps tiling.intrs; - -(** The union of two disjoint tilings is a tiling **) - -goal thy "!!t. t: tiling A ==> \ -\ u: tiling A --> t <= Compl u --> t Un u : tiling A"; -by (etac tiling.induct 1); -by (Simp_tac 1); -by (simp_tac (!simpset addsimps [Un_assoc]) 1); -by (blast_tac (!claset addIs tiling.intrs) 1); -qed_spec_mp "tiling_UnI"; - - -(*** Chess boards ***) - -val [below_0, below_Suc] = nat_recs below_def; -Addsimps [below_0, below_Suc]; - -goal thy "ALL i. (i: below k) = (i finite(evnodd X b) *) -bind_thm("finite_evnodd", evnodd_subset RS finite_subset); - -goalw thy [evnodd_def] "evnodd (A Un B) b = evnodd A b Un evnodd B b"; -by (Blast_tac 1); -qed "evnodd_Un"; - -goalw thy [evnodd_def] "evnodd (A - B) b = evnodd A b - evnodd B b"; -by (Blast_tac 1); -qed "evnodd_Diff"; - -goalw thy [evnodd_def] "evnodd {} b = {}"; -by (Simp_tac 1); -qed "evnodd_empty"; - -goalw thy [evnodd_def] - "evnodd (insert (i,j) C) b = \ -\ (if (i+j) mod 2 = b then insert (i,j) (evnodd C b) else evnodd C b)"; -by (asm_full_simp_tac (!simpset addsimps [evnodd_def] - setloop (split_tac [expand_if] THEN' Step_tac)) 1); -qed "evnodd_insert"; - - -(*** Dominoes ***) - -goal thy "!!d. [| d:domino; b<2 |] ==> EX i j. evnodd d b = {(i,j)}"; -by (eresolve_tac [domino.elim] 1); -by (res_inst_tac [("k1", "i+j")] (mod2_cases RS disjE) 2); -by (res_inst_tac [("k1", "i+j")] (mod2_cases RS disjE) 1); -by (REPEAT_FIRST assume_tac); -(*Four similar cases: case (i+j) mod 2 = b, 2#-b, ...*) -by (REPEAT (asm_full_simp_tac (!simpset addsimps - [less_Suc_eq, evnodd_insert, evnodd_empty, mod_Suc] - setloop split_tac [expand_if]) 1 - THEN Blast_tac 1)); -qed "domino_singleton"; - -goal thy "!!d. d:domino ==> finite d"; -by (blast_tac (!claset addSIs [finite_insertI, finite_emptyI] - addSEs [domino.elim]) 1); -qed "domino_finite"; - - -(*** Tilings of dominoes ***) - -goal thy "!!t. t:tiling domino ==> finite t"; -by (eresolve_tac [tiling.induct] 1); -by (rtac finite_emptyI 1); -by (blast_tac (!claset addSIs [finite_UnI] addIs [domino_finite]) 1); -qed "tiling_domino_finite"; - -goal thy "!!t. t: tiling domino ==> card(evnodd t 0) = card(evnodd t 1)"; -by (eresolve_tac [tiling.induct] 1); -by (simp_tac (!simpset addsimps [evnodd_def]) 1); -by (res_inst_tac [("b1","0")] (domino_singleton RS exE) 1); -by (Simp_tac 2 THEN assume_tac 1); -by (res_inst_tac [("b1","1")] (domino_singleton RS exE) 1); -by (Simp_tac 2 THEN assume_tac 1); -by (Step_tac 1); -by (subgoal_tac "ALL p b. p : evnodd a b --> p ~: evnodd ta b" 1); -by (asm_simp_tac (!simpset addsimps [evnodd_Un, Un_insert_left, - tiling_domino_finite, - evnodd_subset RS finite_subset, - card_insert_disjoint]) 1); -by (blast_tac (!claset addSDs [evnodd_subset RS subsetD] addEs [equalityE]) 1); -qed "tiling_domino_0_1"; - -goal thy "!!m n. [| t = below(Suc m + Suc m) Times below(Suc n + Suc n); \ -\ t' = t - {(0,0)} - {(Suc(m+m), Suc(n+n))} \ -\ |] ==> t' ~: tiling domino"; -by (rtac notI 1); -by (dtac tiling_domino_0_1 1); -by (subgoal_tac "card(evnodd t' 0) < card(evnodd t' 1)" 1); -by (Asm_full_simp_tac 1); -by (subgoal_tac "t : tiling domino" 1); -(*Requires a small simpset that won't move the Suc applications*) -by (asm_simp_tac (HOL_ss addsimps [dominoes_tile_matrix]) 2); -by (subgoal_tac "(m+m)+(n+n) = (m+n)+(m+n)" 1); -by (asm_simp_tac (!simpset addsimps add_ac) 2); -by (asm_full_simp_tac - (!simpset addsimps [evnodd_Diff, evnodd_insert, evnodd_empty, - mod_less, tiling_domino_0_1 RS sym]) 1); -by (rtac less_trans 1); -by (REPEAT - (rtac card_Diff 1 - THEN - asm_simp_tac (!simpset addsimps [tiling_domino_finite, finite_evnodd]) 1 - THEN - asm_simp_tac (!simpset addsimps [mod_less, evnodd_iff]) 1)); -qed "mutil_not_tiling"; - diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/Mutil.thy --- a/src/HOL/ex/Mutil.thy Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,32 +0,0 @@ -(* Title: HOL/ex/Mutil - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1996 University of Cambridge - -The Mutilated Chess Board Problem, formalized inductively - Originator is Max Black, according to J A Robinson. - Popularized as the Mutilated Checkerboard Problem by J McCarthy -*) - -Mutil = Finite + -consts - domino :: "(nat*nat)set set" - tiling :: 'a set set => 'a set set - below :: nat => nat set - evnodd :: "[(nat*nat)set, nat] => (nat*nat)set" - -inductive domino - intrs - horiz "{(i, j), (i, Suc j)} : domino" - vertl "{(i, j), (Suc i, j)} : domino" - -inductive "tiling A" - intrs - empty "{} : tiling A" - Un "[| a: A; t: tiling A; a <= Compl t |] ==> a Un t : tiling A" - -defs - below_def "below n == nat_rec {} insert n" - evnodd_def "evnodd A b == A Int {(i,j). (i+j) mod 2 = b}" - -end diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/Perm.ML --- a/src/HOL/ex/Perm.ML Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,98 +0,0 @@ -(* Title: HOL/ex/Perm.ML - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1995 University of Cambridge - -Permutations: example of an inductive definition -*) - -(*It would be nice to prove - xs <~~> ys = (!x. count xs x = count ys x) -See mset on HOL/ex/Sorting.thy -*) - -open Perm; - -goal Perm.thy "l <~~> l"; -by (list.induct_tac "l" 1); -by (REPEAT (ares_tac perm.intrs 1)); -qed "perm_refl"; - - -(** Some examples of rule induction on permutations **) - -(*The form of the premise lets the induction bind xs and ys.*) -goal Perm.thy "!!xs. xs <~~> ys ==> xs=[] --> ys=[]"; -by (etac perm.induct 1); -by (ALLGOALS Asm_simp_tac); -qed "perm_Nil_lemma"; - -(*A more general version is actually easier to understand!*) -goal Perm.thy "!!xs. xs <~~> ys ==> length(xs) = length(ys)"; -by (etac perm.induct 1); -by (ALLGOALS Asm_simp_tac); -qed "perm_length"; - -goal Perm.thy "!!xs. xs <~~> ys ==> ys <~~> xs"; -by (etac perm.induct 1); -by (REPEAT (ares_tac perm.intrs 1)); -qed "perm_sym"; - -goal Perm.thy "!!xs. [| xs <~~> ys |] ==> x mem xs --> x mem ys"; -by (etac perm.induct 1); -by (Fast_tac 4); -by (ALLGOALS (asm_simp_tac (!simpset setloop split_tac [expand_if]))); -val perm_mem_lemma = result(); - -bind_thm ("perm_mem", perm_mem_lemma RS mp); - -(** Ways of making new permutations **) - -(*We can insert the head anywhere in the list*) -goal Perm.thy "a # xs @ ys <~~> xs @ a # ys"; -by (list.induct_tac "xs" 1); -by (simp_tac (!simpset addsimps [perm_refl]) 1); -by (Simp_tac 1); -by (etac ([perm.swap, perm.Cons] MRS perm.trans) 1); -qed "perm_append_Cons"; - -(*single steps -by (rtac perm.trans 1); -by (rtac perm.swap 1); -by (rtac perm.Cons 1); -*) - -goal Perm.thy "xs@ys <~~> ys@xs"; -by (list.induct_tac "xs" 1); -by (simp_tac (!simpset addsimps [perm_refl]) 1); -by (Simp_tac 1); -by (etac ([perm.Cons, perm_append_Cons] MRS perm.trans) 1); -qed "perm_append_swap"; - - -goal Perm.thy "a # xs <~~> xs @ [a]"; -by (rtac perm.trans 1); -by (rtac perm_append_swap 2); -by (simp_tac (!simpset addsimps [perm_refl]) 1); -qed "perm_append_single"; - -goal Perm.thy "rev xs <~~> xs"; -by (list.induct_tac "xs" 1); -by (simp_tac (!simpset addsimps [perm_refl]) 1); -by (Simp_tac 1); -by (rtac (perm_append_single RS perm_sym RS perm.trans) 1); -by (etac perm.Cons 1); -qed "perm_rev"; - -goal Perm.thy "!!xs. xs <~~> ys ==> l@xs <~~> l@ys"; -by (list.induct_tac "l" 1); -by (Simp_tac 1); -by (asm_simp_tac (!simpset addsimps [perm.Cons]) 1); -qed "perm_append1"; - -goal Perm.thy "!!xs. xs <~~> ys ==> xs@l <~~> ys@l"; -by (rtac (perm_append_swap RS perm.trans) 1); -by (etac (perm_append1 RS perm.trans) 1); -by (rtac perm_append_swap 1); -qed "perm_append2"; - diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/Perm.thy --- a/src/HOL/ex/Perm.thy Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,24 +0,0 @@ -(* Title: HOL/ex/Perm.thy - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1995 University of Cambridge - -Permutations: example of an inductive definition -*) - -Perm = List + - -consts perm :: "('a list * 'a list) set" -syntax "@perm" :: ['a list, 'a list] => bool ("_ <~~> _" [50,50] 50) - -translations - "x <~~> y" == "(x,y) : perm" - -inductive perm - intrs - Nil "[] <~~> []" - swap "y#x#l <~~> x#y#l" - Cons "xs <~~> ys ==> z#xs <~~> z#ys" - trans "[| xs <~~> ys; ys <~~> zs |] ==> xs <~~> zs" - -end diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/PropLog.ML --- a/src/HOL/ex/PropLog.ML Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,229 +0,0 @@ -(* Title: HOL/ex/pl.ML - ID: $Id$ - Author: Tobias Nipkow & Lawrence C Paulson - Copyright 1994 TU Muenchen & University of Cambridge - -Soundness and completeness of propositional logic w.r.t. truth-tables. - -Prove: If H|=p then G|=p where G:Fin(H) -*) - -open PropLog; - -(** Monotonicity **) -goalw PropLog.thy thms.defs "!!G H. G<=H ==> thms(G) <= thms(H)"; -by (rtac lfp_mono 1); -by (REPEAT (ares_tac basic_monos 1)); -qed "thms_mono"; - -(*Rule is called I for Identity Combinator, not for Introduction*) -goal PropLog.thy "H |- p->p"; -by (best_tac (!claset addIs [thms.K,thms.S,thms.MP]) 1); -qed "thms_I"; - -(** Weakening, left and right **) - -(* "[| G<=H; G |- p |] ==> H |- p" - This order of premises is convenient with RS -*) -bind_thm ("weaken_left", (thms_mono RS subsetD)); - -(* H |- p ==> insert(a,H) |- p *) -val weaken_left_insert = subset_insertI RS weaken_left; - -val weaken_left_Un1 = Un_upper1 RS weaken_left; -val weaken_left_Un2 = Un_upper2 RS weaken_left; - -goal PropLog.thy "!!H. H |- q ==> H |- p->q"; -by (fast_tac (!claset addIs [thms.K,thms.MP]) 1); -qed "weaken_right"; - -(*The deduction theorem*) -goal PropLog.thy "!!H. insert p H |- q ==> H |- p->q"; -by (etac thms.induct 1); -by (ALLGOALS - (fast_tac (!claset addIs [thms_I, thms.H, thms.K, thms.S, thms.DN, - thms.S RS thms.MP RS thms.MP, weaken_right]))); -qed "deduction"; - - -(* "[| insert p H |- q; H |- p |] ==> H |- q" - The cut rule - not used -*) -val cut = deduction RS thms.MP; - -(* H |- false ==> H |- p *) -val thms_falseE = weaken_right RS (thms.DN RS thms.MP); - -(* [| H |- p->false; H |- p; q: pl |] ==> H |- q *) -bind_thm ("thms_notE", (thms.MP RS thms_falseE)); - -(** The function eval **) - -goalw PropLog.thy [eval_def] "tt[false] = False"; -by (Simp_tac 1); -qed "eval_false"; - -goalw PropLog.thy [eval_def] "tt[#v] = (v:tt)"; -by (Simp_tac 1); -qed "eval_var"; - -goalw PropLog.thy [eval_def] "tt[p->q] = (tt[p]-->tt[q])"; -by (Simp_tac 1); -qed "eval_imp"; - -Addsimps [eval_false, eval_var, eval_imp]; - -(*Soundness of the rules wrt truth-table semantics*) -goalw PropLog.thy [sat_def] "!!H. H |- p ==> H |= p"; -by (etac thms.induct 1); -by (fast_tac (!claset addSDs [eval_imp RS iffD1 RS mp]) 5); -by (ALLGOALS Asm_simp_tac); -qed "soundness"; - -(*** Towards the completeness proof ***) - -goal PropLog.thy "!!H. H |- p->false ==> H |- p->q"; -by (rtac deduction 1); -by (etac (weaken_left_insert RS thms_notE) 1); -by (rtac thms.H 1); -by (rtac insertI1 1); -qed "false_imp"; - -val [premp,premq] = goal PropLog.thy - "[| H |- p; H |- q->false |] ==> H |- (p->q)->false"; -by (rtac deduction 1); -by (rtac (premq RS weaken_left_insert RS thms.MP) 1); -by (rtac (thms.H RS thms.MP) 1); -by (rtac insertI1 1); -by (rtac (premp RS weaken_left_insert) 1); -qed "imp_false"; - -(*This formulation is required for strong induction hypotheses*) -goal PropLog.thy "hyps p tt |- (if tt[p] then p else p->false)"; -by (rtac (expand_if RS iffD2) 1); -by (PropLog.pl.induct_tac "p" 1); -by (ALLGOALS (simp_tac (!simpset addsimps [thms_I, thms.H]))); -by (fast_tac (!claset addIs [weaken_left_Un1, weaken_left_Un2, - weaken_right, imp_false] - addSEs [false_imp]) 1); -qed "hyps_thms_if"; - -(*Key lemma for completeness; yields a set of assumptions satisfying p*) -val [sat] = goalw PropLog.thy [sat_def] "{} |= p ==> hyps p tt |- p"; -by (rtac (sat RS spec RS mp RS if_P RS subst) 1 THEN - rtac hyps_thms_if 2); -by (Fast_tac 1); -qed "sat_thms_p"; - -(*For proving certain theorems in our new propositional logic*) - -AddSIs [deduction]; -AddIs [thms.H, thms.H RS thms.MP]; - -(*The excluded middle in the form of an elimination rule*) -goal PropLog.thy "H |- (p->q) -> ((p->false)->q) -> q"; -by (rtac (deduction RS deduction) 1); -by (rtac (thms.DN RS thms.MP) 1); -by (ALLGOALS (best_tac (!claset addSIs prems))); -qed "thms_excluded_middle"; - -(*Hard to prove directly because it requires cuts*) -val prems = goal PropLog.thy - "[| insert p H |- q; insert (p->false) H |- q |] ==> H |- q"; -by (rtac (thms_excluded_middle RS thms.MP RS thms.MP) 1); -by (REPEAT (resolve_tac (prems@[deduction]) 1)); -qed "thms_excluded_middle_rule"; - -(*** Completeness -- lemmas for reducing the set of assumptions ***) - -(*For the case hyps(p,t)-insert(#v,Y) |- p; - we also have hyps(p,t)-{#v} <= hyps(p, t-{v}) *) -goal PropLog.thy "hyps p (t-{v}) <= insert (#v->false) ((hyps p t)-{#v})"; -by (PropLog.pl.induct_tac "p" 1); -by (Simp_tac 1); -by (simp_tac (!simpset setloop (split_tac [expand_if])) 1); -by (Simp_tac 1); -by (Fast_tac 1); -qed "hyps_Diff"; - -(*For the case hyps(p,t)-insert(#v -> false,Y) |- p; - we also have hyps(p,t)-{#v->false} <= hyps(p, insert(v,t)) *) -goal PropLog.thy "hyps p (insert v t) <= insert (#v) (hyps p t-{#v->false})"; -by (PropLog.pl.induct_tac "p" 1); -by (Simp_tac 1); -by (simp_tac (!simpset setloop (split_tac [expand_if])) 1); -by (Simp_tac 1); -by (Fast_tac 1); -qed "hyps_insert"; - -(** Two lemmas for use with weaken_left **) - -goal Set.thy "B-C <= insert a (B-insert a C)"; -by (Fast_tac 1); -qed "insert_Diff_same"; - -goal Set.thy "insert a (B-{c}) - D <= insert a (B-insert c D)"; -by (Fast_tac 1); -qed "insert_Diff_subset2"; - -(*The set hyps(p,t) is finite, and elements have the form #v or #v->false; - could probably prove the stronger hyps(p,t) : Fin(hyps(p,{}) Un hyps(p,nat))*) -goal PropLog.thy "hyps p t : Fin(UN v:{x.True}. {#v, #v->false})"; -by (PropLog.pl.induct_tac "p" 1); -by (ALLGOALS (simp_tac (!simpset setloop (split_tac [expand_if])))); -by (ALLGOALS (fast_tac (!claset addSIs Fin.intrs@[Fin_UnI]))); -qed "hyps_finite"; - -val Diff_weaken_left = subset_refl RSN (2, Diff_mono) RS weaken_left; - -(*Induction on the finite set of assumptions hyps(p,t0). - We may repeatedly subtract assumptions until none are left!*) -val [sat] = goal PropLog.thy - "{} |= p ==> !t. hyps p t - hyps p t0 |- p"; -by (rtac (hyps_finite RS Fin_induct) 1); -by (simp_tac (!simpset addsimps [sat RS sat_thms_p]) 1); -by (safe_tac (!claset)); -(*Case hyps(p,t)-insert(#v,Y) |- p *) -by (rtac thms_excluded_middle_rule 1); -by (rtac (insert_Diff_same RS weaken_left) 1); -by (etac spec 1); -by (rtac (insert_Diff_subset2 RS weaken_left) 1); -by (rtac (hyps_Diff RS Diff_weaken_left) 1); -by (etac spec 1); -(*Case hyps(p,t)-insert(#v -> false,Y) |- p *) -by (rtac thms_excluded_middle_rule 1); -by (rtac (insert_Diff_same RS weaken_left) 2); -by (etac spec 2); -by (rtac (insert_Diff_subset2 RS weaken_left) 1); -by (rtac (hyps_insert RS Diff_weaken_left) 1); -by (etac spec 1); -qed "completeness_0_lemma"; - -(*The base case for completeness*) -val [sat] = goal PropLog.thy "{} |= p ==> {} |- p"; -by (rtac (Diff_cancel RS subst) 1); -by (rtac (sat RS (completeness_0_lemma RS spec)) 1); -qed "completeness_0"; - -(*A semantic analogue of the Deduction Theorem*) -goalw PropLog.thy [sat_def] "!!p H. insert p H |= q ==> H |= p->q"; -by (Simp_tac 1); -by (Fast_tac 1); -qed "sat_imp"; - -val [finite] = goal PropLog.thy "H: Fin({p.True}) ==> !p. H |= p --> H |- p"; -by (rtac (finite RS Fin_induct) 1); -by (safe_tac ((claset_of "Fun") addSIs [completeness_0])); -by (rtac (weaken_left_insert RS thms.MP) 1); -by (fast_tac ((claset_of "Fun") addSIs [sat_imp]) 1); -by (Fast_tac 1); -qed "completeness_lemma"; - -val completeness = completeness_lemma RS spec RS mp; - -val [finite] = goal PropLog.thy "H: Fin({p.True}) ==> (H |- p) = (H |= p)"; -by (fast_tac (!claset addSEs [soundness, finite RS completeness]) 1); -qed "thms_iff"; - -writeln"Reached end of file."; diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/PropLog.thy --- a/src/HOL/ex/PropLog.thy Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,46 +0,0 @@ -(* Title: HOL/ex/PropLog.thy - ID: $Id$ - Author: Tobias Nipkow - Copyright 1994 TU Muenchen - -Inductive definition of propositional logic. -*) - -PropLog = Finite + -datatype - 'a pl = false | var 'a ("#_" [1000]) | "->" ('a pl) ('a pl) (infixr 90) -consts - thms :: 'a pl set => 'a pl set - "|-" :: ['a pl set, 'a pl] => bool (infixl 50) - "|=" :: ['a pl set, 'a pl] => bool (infixl 50) - eval2 :: ['a pl, 'a set] => bool - eval :: ['a set, 'a pl] => bool ("_[_]" [100,0] 100) - hyps :: ['a pl, 'a set] => 'a pl set - -translations - "H |- p" == "p : thms(H)" - -inductive "thms(H)" - intrs - H "p:H ==> H |- p" - K "H |- p->q->p" - S "H |- (p->q->r) -> (p->q) -> p->r" - DN "H |- ((p->false) -> false) -> p" - MP "[| H |- p->q; H |- p |] ==> H |- q" - -defs - sat_def "H |= p == (!tt. (!q:H. tt[q]) --> tt[p])" - eval_def "tt[p] == eval2 p tt" - -primrec eval2 pl - "eval2(false) = (%x.False)" - "eval2(#v) = (%tt.v:tt)" - "eval2(p->q) = (%tt.eval2 p tt-->eval2 q tt)" - -primrec hyps pl - "hyps(false) = (%tt.{})" - "hyps(#v) = (%tt.{if v:tt then #v else #v->false})" - "hyps(p->q) = (%tt.hyps p tt Un hyps q tt)" - -end - diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/ROOT.ML --- a/src/HOL/ex/ROOT.ML Wed May 07 13:50:52 1997 +0200 +++ b/src/HOL/ex/ROOT.ML Wed May 07 13:51:22 1997 +0200 @@ -16,22 +16,13 @@ (** time_use "mesontest2.ML"; ULTRA SLOW **) time_use_thy "String"; time_use_thy "BT"; -time_use_thy "Perm"; -time_use_thy "Comb"; time_use_thy "InSort"; time_use_thy "Qsort"; time_use_thy "LexProd"; time_use_thy "Puzzle"; -time_use_thy "Mutil"; time_use_thy "Primes"; time_use_thy "NatSum"; time_use "set.ML"; -time_use_thy "SList"; -time_use_thy "LFilter"; -time_use_thy "Acc"; -time_use_thy "PropLog"; -time_use_thy "Term"; -time_use_thy "Simult"; time_use_thy "MT"; writeln "END: Root file for HOL examples"; diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/SList.ML --- a/src/HOL/ex/SList.ML Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,372 +0,0 @@ -(* Title: HOL/ex/SList.ML - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1993 University of Cambridge - -Definition of type 'a list by a least fixed point -*) - -open SList; - -val list_con_defs = [NIL_def, CONS_def]; - -goal SList.thy "list(A) = {Numb(0)} <+> (A <*> list(A))"; -let val rew = rewrite_rule list_con_defs in -by (fast_tac (!claset addSIs (equalityI :: map rew list.intrs) - addEs [rew list.elim]) 1) -end; -qed "list_unfold"; - -(*This justifies using list in other recursive type definitions*) -goalw SList.thy list.defs "!!A B. A<=B ==> list(A) <= list(B)"; -by (rtac lfp_mono 1); -by (REPEAT (ares_tac basic_monos 1)); -qed "list_mono"; - -(*Type checking -- list creates well-founded sets*) -goalw SList.thy (list_con_defs @ list.defs) "list(sexp) <= sexp"; -by (rtac lfp_lowerbound 1); -by (fast_tac (!claset addIs sexp.intrs@[sexp_In0I,sexp_In1I]) 1); -qed "list_sexp"; - -(* A <= sexp ==> list(A) <= sexp *) -bind_thm ("list_subset_sexp", ([list_mono, list_sexp] MRS subset_trans)); - -(*Induction for the type 'a list *) -val prems = goalw SList.thy [Nil_def,Cons_def] - "[| P(Nil); \ -\ !!x xs. P(xs) ==> P(x # xs) |] ==> P(l)"; -by (rtac (Rep_list_inverse RS subst) 1); (*types force good instantiation*) -by (rtac (Rep_list RS list.induct) 1); -by (REPEAT (ares_tac prems 1 - ORELSE eresolve_tac [rangeE, ssubst, Abs_list_inverse RS subst] 1)); -qed "list_induct2"; - -(*Perform induction on xs. *) -fun list_ind_tac a M = - EVERY [res_inst_tac [("l",a)] list_induct2 M, - rename_last_tac a ["1"] (M+1)]; - -(*** Isomorphisms ***) - -goal SList.thy "inj(Rep_list)"; -by (rtac inj_inverseI 1); -by (rtac Rep_list_inverse 1); -qed "inj_Rep_list"; - -goal SList.thy "inj_onto Abs_list (list(range Leaf))"; -by (rtac inj_onto_inverseI 1); -by (etac Abs_list_inverse 1); -qed "inj_onto_Abs_list"; - -(** Distinctness of constructors **) - -goalw SList.thy list_con_defs "CONS M N ~= NIL"; -by (rtac In1_not_In0 1); -qed "CONS_not_NIL"; -bind_thm ("NIL_not_CONS", (CONS_not_NIL RS not_sym)); - -bind_thm ("CONS_neq_NIL", (CONS_not_NIL RS notE)); -val NIL_neq_CONS = sym RS CONS_neq_NIL; - -goalw SList.thy [Nil_def,Cons_def] "x # xs ~= Nil"; -by (rtac (CONS_not_NIL RS (inj_onto_Abs_list RS inj_onto_contraD)) 1); -by (REPEAT (resolve_tac (list.intrs @ [rangeI, Rep_list]) 1)); -qed "Cons_not_Nil"; - -bind_thm ("Nil_not_Cons", Cons_not_Nil RS not_sym); - -(** Injectiveness of CONS and Cons **) - -goalw SList.thy [CONS_def] "(CONS K M=CONS L N) = (K=L & M=N)"; -by (fast_tac (!claset addSEs [Scons_inject, make_elim In1_inject]) 1); -qed "CONS_CONS_eq"; - -(*For reasoning about abstract list constructors*) -AddIs ([Rep_list] @ list.intrs); - -AddIffs [CONS_not_NIL, NIL_not_CONS, CONS_CONS_eq]; - -AddSDs [inj_onto_Abs_list RS inj_ontoD, - inj_Rep_list RS injD, Leaf_inject]; - -goalw SList.thy [Cons_def] "(x#xs=y#ys) = (x=y & xs=ys)"; -by (Fast_tac 1); -qed "Cons_Cons_eq"; -bind_thm ("Cons_inject2", (Cons_Cons_eq RS iffD1 RS conjE)); - -val [major] = goal SList.thy "CONS M N: list(A) ==> M: A & N: list(A)"; -by (rtac (major RS setup_induction) 1); -by (etac list.induct 1); -by (ALLGOALS (Fast_tac)); -qed "CONS_D"; - -val prems = goalw SList.thy [CONS_def,In1_def] - "CONS M N: sexp ==> M: sexp & N: sexp"; -by (cut_facts_tac prems 1); -by (fast_tac (!claset addSDs [Scons_D]) 1); -qed "sexp_CONS_D"; - - -(*Reasoning about constructors and their freeness*) -Addsimps list.intrs; - -AddIffs [Cons_not_Nil, Nil_not_Cons, Cons_Cons_eq]; - -goal SList.thy "!!N. N: list(A) ==> !M. N ~= CONS M N"; -by (etac list.induct 1); -by (ALLGOALS Asm_simp_tac); -qed "not_CONS_self"; - -goal SList.thy "!x. l ~= x#l"; -by (list_ind_tac "l" 1); -by (ALLGOALS Asm_simp_tac); -qed "not_Cons_self2"; - - -goal SList.thy "(xs ~= []) = (? y ys. xs = y#ys)"; -by (list_ind_tac "xs" 1); -by (Simp_tac 1); -by (Asm_simp_tac 1); -by (REPEAT(resolve_tac [exI,refl,conjI] 1)); -qed "neq_Nil_conv2"; - -(** Conversion rules for List_case: case analysis operator **) - -goalw SList.thy [List_case_def,NIL_def] "List_case c h NIL = c"; -by (rtac Case_In0 1); -qed "List_case_NIL"; - -goalw SList.thy [List_case_def,CONS_def] "List_case c h (CONS M N) = h M N"; -by (simp_tac (!simpset addsimps [Split,Case_In1]) 1); -qed "List_case_CONS"; - -(*** List_rec -- by wf recursion on pred_sexp ***) - -(* The trancl(pred_sexp) is essential because pred_sexp_CONS_I1,2 would not - hold if pred_sexp^+ were changed to pred_sexp. *) - -goal SList.thy - "(%M. List_rec M c d) = wfrec (trancl pred_sexp) \ - \ (%g. List_case c (%x y. d x y (g y)))"; -by (simp_tac (HOL_ss addsimps [List_rec_def]) 1); -val List_rec_unfold = standard - ((wf_pred_sexp RS wf_trancl) RS ((result() RS eq_reflection) RS def_wfrec)); - -(*--------------------------------------------------------------------------- - * Old: - * val List_rec_unfold = [List_rec_def,wf_pred_sexp RS wf_trancl] MRS def_wfrec - * |> standard; - *---------------------------------------------------------------------------*) - -(** pred_sexp lemmas **) - -goalw SList.thy [CONS_def,In1_def] - "!!M. [| M: sexp; N: sexp |] ==> (M, CONS M N) : pred_sexp^+"; -by (Asm_simp_tac 1); -qed "pred_sexp_CONS_I1"; - -goalw SList.thy [CONS_def,In1_def] - "!!M. [| M: sexp; N: sexp |] ==> (N, CONS M N) : pred_sexp^+"; -by (Asm_simp_tac 1); -qed "pred_sexp_CONS_I2"; - -val [prem] = goal SList.thy - "(CONS M1 M2, N) : pred_sexp^+ ==> \ -\ (M1,N) : pred_sexp^+ & (M2,N) : pred_sexp^+"; -by (rtac (prem RS (pred_sexp_subset_Sigma RS trancl_subset_Sigma RS - subsetD RS SigmaE2)) 1); -by (etac (sexp_CONS_D RS conjE) 1); -by (REPEAT (ares_tac [conjI, pred_sexp_CONS_I1, pred_sexp_CONS_I2, - prem RSN (2, trans_trancl RS transD)] 1)); -qed "pred_sexp_CONS_D"; - -(** Conversion rules for List_rec **) - -goal SList.thy "List_rec NIL c h = c"; -by (rtac (List_rec_unfold RS trans) 1); -by (simp_tac (!simpset addsimps [List_case_NIL]) 1); -qed "List_rec_NIL"; - -goal SList.thy "!!M. [| M: sexp; N: sexp |] ==> \ -\ List_rec (CONS M N) c h = h M N (List_rec N c h)"; -by (rtac (List_rec_unfold RS trans) 1); -by (asm_simp_tac (!simpset addsimps [List_case_CONS, pred_sexp_CONS_I2]) 1); -qed "List_rec_CONS"; - -(*** list_rec -- by List_rec ***) - -val Rep_list_in_sexp = - [range_Leaf_subset_sexp RS list_subset_sexp, Rep_list] MRS subsetD; - -local - val list_rec_simps = [List_rec_NIL, List_rec_CONS, - Abs_list_inverse, Rep_list_inverse, - Rep_list, rangeI, inj_Leaf, inv_f_f, - sexp.LeafI, Rep_list_in_sexp] -in - val list_rec_Nil = prove_goalw SList.thy [list_rec_def, Nil_def] - "list_rec Nil c h = c" - (fn _=> [simp_tac (!simpset addsimps list_rec_simps) 1]); - - val list_rec_Cons = prove_goalw SList.thy [list_rec_def, Cons_def] - "list_rec (a#l) c h = h a l (list_rec l c h)" - (fn _=> [simp_tac (!simpset addsimps list_rec_simps) 1]); -end; - -Addsimps [List_rec_NIL, List_rec_CONS, list_rec_Nil, list_rec_Cons]; - - -(*Type checking. Useful?*) -val major::A_subset_sexp::prems = goal SList.thy - "[| M: list(A); \ -\ A<=sexp; \ -\ c: C(NIL); \ -\ !!x y r. [| x: A; y: list(A); r: C(y) |] ==> h x y r: C(CONS x y) \ -\ |] ==> List_rec M c h : C(M :: 'a item)"; -val sexp_ListA_I = A_subset_sexp RS list_subset_sexp RS subsetD; -val sexp_A_I = A_subset_sexp RS subsetD; -by (rtac (major RS list.induct) 1); -by (ALLGOALS(asm_simp_tac (!simpset addsimps ([sexp_A_I,sexp_ListA_I]@prems)))); -qed "List_rec_type"; - -(** Generalized map functionals **) - -goalw SList.thy [Rep_map_def] "Rep_map f Nil = NIL"; -by (rtac list_rec_Nil 1); -qed "Rep_map_Nil"; - -goalw SList.thy [Rep_map_def] - "Rep_map f (x#xs) = CONS (f x) (Rep_map f xs)"; -by (rtac list_rec_Cons 1); -qed "Rep_map_Cons"; - -goalw SList.thy [Rep_map_def] "!!f. (!!x. f(x): A) ==> Rep_map f xs: list(A)"; -by (rtac list_induct2 1); -by (ALLGOALS Asm_simp_tac); -qed "Rep_map_type"; - -goalw SList.thy [Abs_map_def] "Abs_map g NIL = Nil"; -by (rtac List_rec_NIL 1); -qed "Abs_map_NIL"; - -val prems = goalw SList.thy [Abs_map_def] - "[| M: sexp; N: sexp |] ==> \ -\ Abs_map g (CONS M N) = g(M) # Abs_map g N"; -by (REPEAT (resolve_tac (List_rec_CONS::prems) 1)); -qed "Abs_map_CONS"; - -(*These 2 rules ease the use of primitive recursion. NOTE USE OF == *) -val [rew] = goal SList.thy - "[| !!xs. f(xs) == list_rec xs c h |] ==> f([]) = c"; -by (rewtac rew); -by (rtac list_rec_Nil 1); -qed "def_list_rec_Nil"; - -val [rew] = goal SList.thy - "[| !!xs. f(xs) == list_rec xs c h |] ==> f(x#xs) = h x xs (f xs)"; -by (rewtac rew); -by (rtac list_rec_Cons 1); -qed "def_list_rec_Cons"; - -fun list_recs def = - [standard (def RS def_list_rec_Nil), - standard (def RS def_list_rec_Cons)]; - -(*** Unfolding the basic combinators ***) - -val [null_Nil, null_Cons] = list_recs null_def; -val [_, hd_Cons] = list_recs hd_def; -val [_, tl_Cons] = list_recs tl_def; -val [ttl_Nil, ttl_Cons] = list_recs ttl_def; -val [append_Nil3, append_Cons] = list_recs append_def; -val [mem_Nil, mem_Cons] = list_recs mem_def; -val [set_of_list_Nil, set_of_list_Cons] = list_recs set_of_list_def; -val [map_Nil, map_Cons] = list_recs map_def; -val [list_case_Nil, list_case_Cons] = list_recs list_case_def; -val [filter_Nil, filter_Cons] = list_recs filter_def; - -Addsimps - [null_Nil, ttl_Nil, - mem_Nil, mem_Cons, - list_case_Nil, list_case_Cons, - append_Nil3, append_Cons, - set_of_list_Nil, set_of_list_Cons, - map_Nil, map_Cons, - filter_Nil, filter_Cons]; - - -(** @ - append **) - -goal SList.thy "(xs@ys)@zs = xs@(ys@zs)"; -by (list_ind_tac "xs" 1); -by (ALLGOALS Asm_simp_tac); -qed "append_assoc2"; - -goal SList.thy "xs @ [] = xs"; -by (list_ind_tac "xs" 1); -by (ALLGOALS Asm_simp_tac); -qed "append_Nil4"; - -(** mem **) - -goal SList.thy "x mem (xs@ys) = (x mem xs | x mem ys)"; -by (list_ind_tac "xs" 1); -by (ALLGOALS(asm_simp_tac (!simpset setloop (split_tac [expand_if])))); -qed "mem_append2"; - -goal SList.thy "x mem [x:xs.P(x)] = (x mem xs & P(x))"; -by (list_ind_tac "xs" 1); -by (ALLGOALS(asm_simp_tac (!simpset setloop (split_tac [expand_if])))); -qed "mem_filter2"; - - -(** The functional "map" **) - -Addsimps [Rep_map_Nil, Rep_map_Cons, Abs_map_NIL, Abs_map_CONS]; - -val [major,A_subset_sexp,minor] = goal SList.thy - "[| M: list(A); A<=sexp; !!z. z: A ==> f(g(z)) = z |] \ -\ ==> Rep_map f (Abs_map g M) = M"; -by (rtac (major RS list.induct) 1); -by (ALLGOALS (asm_simp_tac (!simpset addsimps [sexp_A_I,sexp_ListA_I,minor]))); -qed "Abs_map_inverse"; - -(*Rep_map_inverse is obtained via Abs_Rep_map and map_ident*) - -(** list_case **) - -goal SList.thy - "P(list_case a f xs) = ((xs=[] --> P(a)) & \ -\ (!y ys. xs=y#ys --> P(f y ys)))"; -by (list_ind_tac "xs" 1); -by (ALLGOALS Asm_simp_tac); -by (Fast_tac 1); -qed "expand_list_case2"; - - -(** Additional mapping lemmas **) - -goal SList.thy "map (%x.x) xs = xs"; -by (list_ind_tac "xs" 1); -by (ALLGOALS Asm_simp_tac); -qed "map_ident2"; - -goal SList.thy "map f (xs@ys) = map f xs @ map f ys"; -by (list_ind_tac "xs" 1); -by (ALLGOALS Asm_simp_tac); -qed "map_append2"; - -goalw SList.thy [o_def] "map (f o g) xs = map f (map g xs)"; -by (list_ind_tac "xs" 1); -by (ALLGOALS Asm_simp_tac); -qed "map_compose2"; - -goal SList.thy "!!f. (!!x. f(x): sexp) ==> \ -\ Abs_map g (Rep_map f xs) = map (%t. g(f(t))) xs"; -by (list_ind_tac "xs" 1); -by (ALLGOALS(asm_simp_tac(!simpset addsimps - [Rep_map_type,list_sexp RS subsetD]))); -qed "Abs_Rep_map"; - -Addsimps [append_Nil4, map_ident2]; diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/SList.thy --- a/src/HOL/ex/SList.thy Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,119 +0,0 @@ -(* Title: HOL/ex/SList.thy - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1993 University of Cambridge - -Definition of type 'a list (strict lists) by a least fixed point - -We use list(A) == lfp(%Z. {NUMB(0)} <+> A <*> Z) -and not list == lfp(%Z. {NUMB(0)} <+> range(Leaf) <*> Z) -so that list can serve as a "functor" for defining other recursive types -*) - -SList = Sexp + - -types - 'a list - -arities - list :: (term) term - - -consts - - list :: 'a item set => 'a item set - Rep_list :: 'a list => 'a item - Abs_list :: 'a item => 'a list - NIL :: 'a item - CONS :: ['a item, 'a item] => 'a item - Nil :: 'a list - "#" :: ['a, 'a list] => 'a list (infixr 65) - List_case :: ['b, ['a item, 'a item]=>'b, 'a item] => 'b - List_rec :: ['a item, 'b, ['a item, 'a item, 'b]=>'b] => 'b - list_case :: ['b, ['a, 'a list]=>'b, 'a list] => 'b - list_rec :: ['a list, 'b, ['a, 'a list, 'b]=>'b] => 'b - Rep_map :: ('b => 'a item) => ('b list => 'a item) - Abs_map :: ('a item => 'b) => 'a item => 'b list - null :: 'a list => bool - hd :: 'a list => 'a - tl,ttl :: 'a list => 'a list - set_of_list :: ('a list => 'a set) - mem :: ['a, 'a list] => bool (infixl 55) - map :: ('a=>'b) => ('a list => 'b list) - "@" :: ['a list, 'a list] => 'a list (infixr 65) - filter :: ['a => bool, 'a list] => 'a list - - (* list Enumeration *) - - "[]" :: 'a list ("[]") - "@list" :: args => 'a list ("[(_)]") - - (* Special syntax for filter *) - "@filter" :: [idt, 'a list, bool] => 'a list ("(1[_:_ ./ _])") - -translations - "[x, xs]" == "x#[xs]" - "[x]" == "x#[]" - "[]" == "Nil" - - "case xs of Nil => a | y#ys => b" == "list_case a (%y ys.b) xs" - - "[x:xs . P]" == "filter (%x.P) xs" - -defs - (* Defining the Concrete Constructors *) - NIL_def "NIL == In0(Numb(0))" - CONS_def "CONS M N == In1(M $ N)" - -inductive "list(A)" - intrs - NIL_I "NIL: list(A)" - CONS_I "[| a: A; M: list(A) |] ==> CONS a M : list(A)" - -rules - (* Faking a Type Definition ... *) - Rep_list "Rep_list(xs): list(range(Leaf))" - Rep_list_inverse "Abs_list(Rep_list(xs)) = xs" - Abs_list_inverse "M: list(range(Leaf)) ==> Rep_list(Abs_list(M)) = M" - - -defs - (* Defining the Abstract Constructors *) - Nil_def "Nil == Abs_list(NIL)" - Cons_def "x#xs == Abs_list(CONS (Leaf x) (Rep_list xs))" - - List_case_def "List_case c d == Case (%x.c) (Split d)" - - (* list Recursion -- the trancl is Essential; see list.ML *) - - List_rec_def - "List_rec M c d == wfrec (trancl pred_sexp) - (%g. List_case c (%x y. d x y (g y))) M" - - list_rec_def - "list_rec l c d == - List_rec (Rep_list l) c (%x y r. d (inv Leaf x) (Abs_list y) r)" - - (* Generalized Map Functionals *) - - Rep_map_def "Rep_map f xs == list_rec xs NIL (%x l r. CONS (f x) r)" - Abs_map_def "Abs_map g M == List_rec M Nil (%N L r. g(N)#r)" - - null_def "null(xs) == list_rec xs True (%x xs r.False)" - hd_def "hd(xs) == list_rec xs (@x.True) (%x xs r.x)" - tl_def "tl(xs) == list_rec xs (@xs.True) (%x xs r.xs)" - (* a total version of tl: *) - ttl_def "ttl(xs) == list_rec xs [] (%x xs r.xs)" - - set_of_list_def "set_of_list xs == list_rec xs {} (%x l r. insert x r)" - - mem_def "x mem xs == - list_rec xs False (%y ys r. if y=x then True else r)" - map_def "map f xs == list_rec xs [] (%x l r. f(x)#r)" - append_def "xs@ys == list_rec xs ys (%x l r. x#r)" - filter_def "filter P xs == - list_rec xs [] (%x xs r. if P(x) then x#r else r)" - - list_case_def "list_case a f xs == list_rec xs a (%x xs r.f x xs)" - -end diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/Simult.ML --- a/src/HOL/ex/Simult.ML Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,298 +0,0 @@ -(* Title: HOL/ex/Simult.ML - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1993 University of Cambridge - -Primitives for simultaneous recursive type definitions - includes worked example of trees & forests - -This is essentially the same data structure that on ex/term.ML, which is -simpler because it uses list as a new type former. The approach in this -file may be superior for other simultaneous recursions. -*) - -open Simult; - -(*** Monotonicity and unfolding of the function ***) - -goal Simult.thy "mono(%Z. A <*> Part Z In1 \ -\ <+> ({Numb(0)} <+> Part Z In0 <*> Part Z In1))"; -by (REPEAT (ares_tac [monoI, subset_refl, usum_mono, uprod_mono, - Part_mono] 1)); -qed "TF_fun_mono"; - -val TF_unfold = TF_fun_mono RS (TF_def RS def_lfp_Tarski); - -goalw Simult.thy [TF_def] "!!A B. A<=B ==> TF(A) <= TF(B)"; -by (REPEAT (ares_tac [lfp_mono, subset_refl, usum_mono, uprod_mono] 1)); -qed "TF_mono"; - -goalw Simult.thy [TF_def] "TF(sexp) <= sexp"; -by (rtac lfp_lowerbound 1); -by (blast_tac (!claset addIs sexp.intrs@[sexp_In0I, sexp_In1I] - addSEs [PartE]) 1); -qed "TF_sexp"; - -(* A <= sexp ==> TF(A) <= sexp *) -val TF_subset_sexp = standard - (TF_mono RS (TF_sexp RSN (2,subset_trans))); - - -(** Elimination -- structural induction on the set TF **) - -val TF_Rep_defs = [TCONS_def,FNIL_def,FCONS_def,NIL_def,CONS_def]; - -val major::prems = goalw Simult.thy TF_Rep_defs - "[| i: TF(A); \ -\ !!M N. [| M: A; N: Part (TF A) In1; R(N) |] ==> R(TCONS M N); \ -\ R(FNIL); \ -\ !!M N. [| M: Part (TF A) In0; N: Part (TF A) In1; R(M); R(N) \ -\ |] ==> R(FCONS M N) \ -\ |] ==> R(i)"; -by (rtac ([TF_def, TF_fun_mono, major] MRS def_induct) 1); -by (blast_tac (!claset addIs (prems@[PartI]) - addEs [usumE, uprodE, PartE]) 1); -qed "TF_induct"; - -(*This lemma replaces a use of subgoal_tac to prove tree_forest_induct*) -goalw Simult.thy [Part_def] - "!!A. ! M: TF(A). (M: Part (TF A) In0 --> P(M)) & \ -\ (M: Part (TF A) In1 --> Q(M)) \ -\ ==> (! M: Part (TF A) In0. P(M)) & (! M: Part (TF A) In1. Q(M))"; -by (Blast_tac 1); -qed "TF_induct_lemma"; - -(*Could prove ~ TCONS M N : Part (TF A) In1 etc. *) - -(*Induction on TF with separate predicates P, Q*) -val prems = goalw Simult.thy TF_Rep_defs - "[| !!M N. [| M: A; N: Part (TF A) In1; Q(N) |] ==> P(TCONS M N); \ -\ Q(FNIL); \ -\ !!M N. [| M: Part (TF A) In0; N: Part (TF A) In1; P(M); Q(N) \ -\ |] ==> Q(FCONS M N) \ -\ |] ==> (! M: Part (TF A) In0. P(M)) & (! N: Part (TF A) In1. Q(N))"; -by (rtac (ballI RS TF_induct_lemma) 1); -by (etac TF_induct 1); -by (rewrite_goals_tac TF_Rep_defs); - (*Blast_tac needs this type instantiation in order to preserve the - right overloading of equality. The injectiveness properties for - type 'a item hold only for set types.*) -val PartE' = read_instantiate [("'a", "?'c set")] PartE; -by (ALLGOALS (blast_tac (!claset addSEs [PartE'] addIs prems))); -qed "Tree_Forest_induct"; - -(*Induction for the abstract types 'a tree, 'a forest*) -val prems = goalw Simult.thy [Tcons_def,Fnil_def,Fcons_def] - "[| !!x ts. Q(ts) ==> P(Tcons x ts); \ -\ Q(Fnil); \ -\ !!t ts. [| P(t); Q(ts) |] ==> Q(Fcons t ts) \ -\ |] ==> (! t. P(t)) & (! ts. Q(ts))"; -by (res_inst_tac [("P1","%z.P(Abs_Tree(z))"), - ("Q1","%z.Q(Abs_Forest(z))")] - (Tree_Forest_induct RS conjE) 1); -(*Instantiates ?A1 to range(Leaf). *) -by (fast_tac (!claset addSEs [Rep_Tree_inverse RS subst, - Rep_Forest_inverse RS subst] - addSIs [Rep_Tree,Rep_Forest]) 4); -(*Cannot use simplifier: the rewrites work in the wrong direction!*) -by (ALLGOALS (fast_tac (!claset addSEs [Abs_Tree_inverse RS subst, - Abs_Forest_inverse RS subst] - addSIs prems))); -qed "tree_forest_induct"; - - - -(*** Isomorphisms ***) - -goal Simult.thy "inj(Rep_Tree)"; -by (rtac inj_inverseI 1); -by (rtac Rep_Tree_inverse 1); -qed "inj_Rep_Tree"; - -goal Simult.thy "inj_onto Abs_Tree (Part (TF(range Leaf)) In0)"; -by (rtac inj_onto_inverseI 1); -by (etac Abs_Tree_inverse 1); -qed "inj_onto_Abs_Tree"; - -goal Simult.thy "inj(Rep_Forest)"; -by (rtac inj_inverseI 1); -by (rtac Rep_Forest_inverse 1); -qed "inj_Rep_Forest"; - -goal Simult.thy "inj_onto Abs_Forest (Part (TF(range Leaf)) In1)"; -by (rtac inj_onto_inverseI 1); -by (etac Abs_Forest_inverse 1); -qed "inj_onto_Abs_Forest"; - -(** Introduction rules for constructors **) - -(* c : A <*> Part (TF A) In1 - <+> {Numb(0)} <+> Part (TF A) In0 <*> Part (TF A) In1 ==> c : TF(A) *) -val TF_I = TF_unfold RS equalityD2 RS subsetD; - -(*For reasoning about the representation*) -AddIs [TF_I, uprodI, usum_In0I, usum_In1I]; -AddSEs [Scons_inject]; - -goalw Simult.thy TF_Rep_defs - "!!A. [| a: A; M: Part (TF A) In1 |] ==> TCONS a M : Part (TF A) In0"; -by (Blast_tac 1); -qed "TCONS_I"; - -(* FNIL is a TF(A) -- this also justifies the type definition*) -goalw Simult.thy TF_Rep_defs "FNIL: Part (TF A) In1"; -by (Blast_tac 1); -qed "FNIL_I"; - -goalw Simult.thy TF_Rep_defs - "!!A. [| M: Part (TF A) In0; N: Part (TF A) In1 |] ==> \ -\ FCONS M N : Part (TF A) In1"; -by (Blast_tac 1); -qed "FCONS_I"; - -(** Injectiveness of TCONS and FCONS **) - -goalw Simult.thy TF_Rep_defs "(TCONS K M=TCONS L N) = (K=L & M=N)"; -by (Blast_tac 1); -qed "TCONS_TCONS_eq"; -bind_thm ("TCONS_inject", (TCONS_TCONS_eq RS iffD1 RS conjE)); - -goalw Simult.thy TF_Rep_defs "(FCONS K M=FCONS L N) = (K=L & M=N)"; -by (Blast_tac 1); -qed "FCONS_FCONS_eq"; -bind_thm ("FCONS_inject", (FCONS_FCONS_eq RS iffD1 RS conjE)); - -(** Distinctness of TCONS, FNIL and FCONS **) - -goalw Simult.thy TF_Rep_defs "TCONS M N ~= FNIL"; -by (Blast_tac 1); -qed "TCONS_not_FNIL"; -bind_thm ("FNIL_not_TCONS", (TCONS_not_FNIL RS not_sym)); - -bind_thm ("TCONS_neq_FNIL", (TCONS_not_FNIL RS notE)); -val FNIL_neq_TCONS = sym RS TCONS_neq_FNIL; - -goalw Simult.thy TF_Rep_defs "FCONS M N ~= FNIL"; -by (Blast_tac 1); -qed "FCONS_not_FNIL"; -bind_thm ("FNIL_not_FCONS", (FCONS_not_FNIL RS not_sym)); - -bind_thm ("FCONS_neq_FNIL", (FCONS_not_FNIL RS notE)); -val FNIL_neq_FCONS = sym RS FCONS_neq_FNIL; - -goalw Simult.thy TF_Rep_defs "TCONS M N ~= FCONS K L"; -by (Blast_tac 1); -qed "TCONS_not_FCONS"; -bind_thm ("FCONS_not_TCONS", (TCONS_not_FCONS RS not_sym)); - -bind_thm ("TCONS_neq_FCONS", (TCONS_not_FCONS RS notE)); -val FCONS_neq_TCONS = sym RS TCONS_neq_FCONS; - -(*???? Too many derived rules ???? - Automatically generate symmetric forms? Always expand TF_Rep_defs? *) - -(** Injectiveness of Tcons and Fcons **) - -(*For reasoning about abstract constructors*) -AddSIs [Rep_Tree, Rep_Forest, TCONS_I, FNIL_I, FCONS_I]; -AddSEs [TCONS_inject, FCONS_inject, - TCONS_neq_FNIL, FNIL_neq_TCONS, - FCONS_neq_FNIL, FNIL_neq_FCONS, - TCONS_neq_FCONS, FCONS_neq_TCONS]; -AddSDs [inj_onto_Abs_Tree RS inj_ontoD, - inj_onto_Abs_Forest RS inj_ontoD, - inj_Rep_Tree RS injD, inj_Rep_Forest RS injD, - Leaf_inject]; - -goalw Simult.thy [Tcons_def] "(Tcons x xs=Tcons y ys) = (x=y & xs=ys)"; -by (Blast_tac 1); -qed "Tcons_Tcons_eq"; -bind_thm ("Tcons_inject", (Tcons_Tcons_eq RS iffD1 RS conjE)); - -goalw Simult.thy [Fcons_def,Fnil_def] "Fcons x xs ~= Fnil"; -by (Blast_tac 1); -qed "Fcons_not_Fnil"; - -bind_thm ("Fcons_neq_Fnil", Fcons_not_Fnil RS notE); -val Fnil_neq_Fcons = sym RS Fcons_neq_Fnil; - - -(** Injectiveness of Fcons **) - -goalw Simult.thy [Fcons_def] "(Fcons x xs=Fcons y ys) = (x=y & xs=ys)"; -by (Blast_tac 1); -qed "Fcons_Fcons_eq"; -bind_thm ("Fcons_inject", Fcons_Fcons_eq RS iffD1 RS conjE); - - -(*** TF_rec -- by wf recursion on pred_sexp ***) - -goal Simult.thy - "(%M. TF_rec M b c d) = wfrec (trancl pred_sexp) \ - \ (%g. Case (Split(%x y. b x y (g y))) \ - \ (List_case c (%x y. d x y (g x) (g y))))"; -by (simp_tac (HOL_ss addsimps [TF_rec_def]) 1); -val TF_rec_unfold = (wf_pred_sexp RS wf_trancl) RS - ((result() RS eq_reflection) RS def_wfrec); - -(*--------------------------------------------------------------------------- - * Old: - * val TF_rec_unfold = - * wf_pred_sexp RS wf_trancl RS (TF_rec_def RS def_wfrec); - *---------------------------------------------------------------------------*) - -(** conversion rules for TF_rec **) - -goalw Simult.thy [TCONS_def] - "!!M N. [| M: sexp; N: sexp |] ==> \ -\ TF_rec (TCONS M N) b c d = b M N (TF_rec N b c d)"; -by (rtac (TF_rec_unfold RS trans) 1); -by (simp_tac (!simpset addsimps [Case_In0, Split]) 1); -by (asm_simp_tac (!simpset addsimps [In0_def]) 1); -qed "TF_rec_TCONS"; - -goalw Simult.thy [FNIL_def] "TF_rec FNIL b c d = c"; -by (rtac (TF_rec_unfold RS trans) 1); -by (simp_tac (HOL_ss addsimps [Case_In1, List_case_NIL]) 1); -qed "TF_rec_FNIL"; - -goalw Simult.thy [FCONS_def] - "!!M N. [| M: sexp; N: sexp |] ==> \ -\ TF_rec (FCONS M N) b c d = d M N (TF_rec M b c d) (TF_rec N b c d)"; -by (rtac (TF_rec_unfold RS trans) 1); -by (simp_tac (HOL_ss addsimps [Case_In1, List_case_CONS]) 1); -by (asm_simp_tac (!simpset addsimps [CONS_def,In1_def]) 1); -qed "TF_rec_FCONS"; - - -(*** tree_rec, forest_rec -- by TF_rec ***) - -val Rep_Tree_in_sexp = - [range_Leaf_subset_sexp RS TF_subset_sexp RS (Part_subset RS subset_trans), - Rep_Tree] MRS subsetD; -val Rep_Forest_in_sexp = - [range_Leaf_subset_sexp RS TF_subset_sexp RS (Part_subset RS subset_trans), - Rep_Forest] MRS subsetD; - -val tf_rec_ss = HOL_ss addsimps - [TF_rec_TCONS, TF_rec_FNIL, TF_rec_FCONS, - TCONS_I, FNIL_I, FCONS_I, Rep_Tree, Rep_Forest, - Rep_Tree_inverse, Rep_Forest_inverse, - Abs_Tree_inverse, Abs_Forest_inverse, - inj_Leaf, inv_f_f, sexp.LeafI, range_eqI, - Rep_Tree_in_sexp, Rep_Forest_in_sexp]; - -goalw Simult.thy [tree_rec_def, forest_rec_def, Tcons_def] - "tree_rec (Tcons a tf) b c d = b a tf (forest_rec tf b c d)"; -by (simp_tac tf_rec_ss 1); -qed "tree_rec_Tcons"; - -goalw Simult.thy [forest_rec_def, Fnil_def] "forest_rec Fnil b c d = c"; -by (simp_tac tf_rec_ss 1); -qed "forest_rec_Fnil"; - -goalw Simult.thy [tree_rec_def, forest_rec_def, Fcons_def] - "forest_rec (Fcons t tf) b c d = \ -\ d t tf (tree_rec t b c d) (forest_rec tf b c d)"; -by (simp_tac tf_rec_ss 1); -qed "forest_rec_Cons"; diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/Simult.thy --- a/src/HOL/ex/Simult.thy Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,82 +0,0 @@ -(* Title: HOL/ex/Simult - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1993 University of Cambridge - -A simultaneous recursive type definition: trees & forests - -This is essentially the same data structure that on ex/term.ML, which is -simpler because it uses list as a new type former. The approach in this -file may be superior for other simultaneous recursions. - -The inductive definition package does not help defining this sort of mutually -recursive data structure because it uses Inl, Inr instead of In0, In1. -*) - -Simult = SList + - -types 'a tree - 'a forest - -arities tree,forest :: (term)term - -consts - TF :: 'a item set => 'a item set - FNIL :: 'a item - TCONS,FCONS :: ['a item, 'a item] => 'a item - Rep_Tree :: 'a tree => 'a item - Abs_Tree :: 'a item => 'a tree - Rep_Forest :: 'a forest => 'a item - Abs_Forest :: 'a item => 'a forest - Tcons :: ['a, 'a forest] => 'a tree - Fcons :: ['a tree, 'a forest] => 'a forest - Fnil :: 'a forest - TF_rec :: ['a item, ['a item , 'a item, 'b]=>'b, - 'b, ['a item , 'a item, 'b, 'b]=>'b] => 'b - tree_rec :: ['a tree, ['a, 'a forest, 'b]=>'b, - 'b, ['a tree, 'a forest, 'b, 'b]=>'b] => 'b - forest_rec :: ['a forest, ['a, 'a forest, 'b]=>'b, - 'b, ['a tree, 'a forest, 'b, 'b]=>'b] => 'b - -defs - (*the concrete constants*) - TCONS_def "TCONS M N == In0(M $ N)" - FNIL_def "FNIL == In1(NIL)" - FCONS_def "FCONS M N == In1(CONS M N)" - (*the abstract constants*) - Tcons_def "Tcons a ts == Abs_Tree(TCONS (Leaf a) (Rep_Forest ts))" - Fnil_def "Fnil == Abs_Forest(FNIL)" - Fcons_def "Fcons t ts == Abs_Forest(FCONS (Rep_Tree t) (Rep_Forest ts))" - - TF_def "TF(A) == lfp(%Z. A <*> Part Z In1 - <+> ({Numb(0)} <+> Part Z In0 <*> Part Z In1))" - -rules - (*faking a type definition for tree...*) - Rep_Tree "Rep_Tree(n): Part (TF(range Leaf)) In0" - Rep_Tree_inverse "Abs_Tree(Rep_Tree(t)) = t" - Abs_Tree_inverse "z: Part (TF(range Leaf)) In0 ==> Rep_Tree(Abs_Tree(z)) = z" - (*faking a type definition for forest...*) - Rep_Forest "Rep_Forest(n): Part (TF(range Leaf)) In1" - Rep_Forest_inverse "Abs_Forest(Rep_Forest(ts)) = ts" - Abs_Forest_inverse - "z: Part (TF(range Leaf)) In1 ==> Rep_Forest(Abs_Forest(z)) = z" - - -defs - (*recursion*) - TF_rec_def - "TF_rec M b c d == wfrec (trancl pred_sexp) - (%g. Case (Split(%x y. b x y (g y))) - (List_case c (%x y. d x y (g x) (g y)))) M" - - tree_rec_def - "tree_rec t b c d == - TF_rec (Rep_Tree t) (%x y r. b (inv Leaf x) (Abs_Forest y) r) - c (%x y rt rf. d (Abs_Tree x) (Abs_Forest y) rt rf)" - - forest_rec_def - "forest_rec tf b c d == - TF_rec (Rep_Forest tf) (%x y r. b (inv Leaf x) (Abs_Forest y) r) - c (%x y rt rf. d (Abs_Tree x) (Abs_Forest y) rt rf)" -end diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/Term.ML --- a/src/HOL/ex/Term.ML Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,172 +0,0 @@ -(* Title: HOL/ex/Term - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1992 University of Cambridge - -Terms over a given alphabet -- function applications; illustrates list functor - (essentially the same type as in Trees & Forests) -*) - -open Term; - -(*** Monotonicity and unfolding of the function ***) - -goal Term.thy "term(A) = A <*> list(term(A))"; -by (fast_tac (!claset addSIs (equalityI :: term.intrs) - addEs [term.elim]) 1); -qed "term_unfold"; - -(*This justifies using term in other recursive type definitions*) -goalw Term.thy term.defs "!!A B. A<=B ==> term(A) <= term(B)"; -by (REPEAT (ares_tac ([lfp_mono, list_mono] @ basic_monos) 1)); -qed "term_mono"; - -(** Type checking -- term creates well-founded sets **) - -goalw Term.thy term.defs "term(sexp) <= sexp"; -by (rtac lfp_lowerbound 1); -by (fast_tac (!claset addIs [sexp.SconsI, list_sexp RS subsetD]) 1); -qed "term_sexp"; - -(* A <= sexp ==> term(A) <= sexp *) -bind_thm ("term_subset_sexp", ([term_mono, term_sexp] MRS subset_trans)); - - -(** Elimination -- structural induction on the set term(A) **) - -(*Induction for the set term(A) *) -val [major,minor] = goal Term.thy - "[| M: term(A); \ -\ !!x zs. [| x: A; zs: list(term(A)); zs: list({x.R(x)}) \ -\ |] ==> R(x$zs) \ -\ |] ==> R(M)"; -by (rtac (major RS term.induct) 1); -by (REPEAT (eresolve_tac ([minor] @ - ([Int_lower1,Int_lower2] RL [list_mono RS subsetD])) 1)); -(*Proof could also use mono_Int RS subsetD RS IntE *) -qed "Term_induct"; - -(*Induction on term(A) followed by induction on list *) -val major::prems = goal Term.thy - "[| M: term(A); \ -\ !!x. [| x: A |] ==> R(x$NIL); \ -\ !!x z zs. [| x: A; z: term(A); zs: list(term(A)); R(x$zs) \ -\ |] ==> R(x $ CONS z zs) \ -\ |] ==> R(M)"; -by (rtac (major RS Term_induct) 1); -by (etac list.induct 1); -by (REPEAT (ares_tac prems 1)); -qed "Term_induct2"; - -(*** Structural Induction on the abstract type 'a term ***) - -val Rep_term_in_sexp = - Rep_term RS (range_Leaf_subset_sexp RS term_subset_sexp RS subsetD); - -(*Induction for the abstract type 'a term*) -val prems = goalw Term.thy [App_def,Rep_Tlist_def,Abs_Tlist_def] - "[| !!x ts. (ALL t: set_of_list ts. R t) ==> R(App x ts) \ -\ |] ==> R(t)"; -by (rtac (Rep_term_inverse RS subst) 1); (*types force good instantiation*) -by (res_inst_tac [("P","Rep_term(t) : sexp")] conjunct2 1); -by (rtac (Rep_term RS Term_induct) 1); -by (REPEAT (ares_tac [conjI, sexp.SconsI, term_subset_sexp RS - list_subset_sexp, range_Leaf_subset_sexp] 1 - ORELSE etac rev_subsetD 1)); -by (eres_inst_tac [("A1","term(?u)"), ("f1","Rep_term"), ("g1","Abs_term")] - (Abs_map_inverse RS subst) 1); -by (rtac (range_Leaf_subset_sexp RS term_subset_sexp) 1); -by (etac Abs_term_inverse 1); -by (etac rangeE 1); -by (hyp_subst_tac 1); -by (resolve_tac prems 1); -by (etac list.induct 1); -by (etac CollectE 2); -by (stac Abs_map_CONS 2); -by (etac conjunct1 2); -by (etac rev_subsetD 2); -by (rtac list_subset_sexp 2); -by (ALLGOALS Asm_simp_tac); -by (ALLGOALS Fast_tac); -qed "term_induct"; - -(*Induction for the abstract type 'a term*) -val prems = goal Term.thy - "[| !!x. R(App x Nil); \ -\ !!x t ts. R(App x ts) ==> R(App x (t#ts)) \ -\ |] ==> R(t)"; -by (rtac term_induct 1); (*types force good instantiation*) -by (etac rev_mp 1); -by (rtac list_induct2 1); (*types force good instantiation*) -by (ALLGOALS (asm_simp_tac (!simpset addsimps prems))); -qed "term_induct2"; - -(*Perform induction on xs. *) -fun term_ind2_tac a i = - EVERY [res_inst_tac [("t",a)] term_induct2 i, - rename_last_tac a ["1","s"] (i+1)]; - - - -(*** Term_rec -- by wf recursion on pred_sexp ***) - -goal Term.thy - "(%M. Term_rec M d) = wfrec (trancl pred_sexp) \ - \ (%g. Split(%x y. d x y (Abs_map g y)))"; -by (simp_tac (HOL_ss addsimps [Term_rec_def]) 1); -bind_thm("Term_rec_unfold", (wf_pred_sexp RS wf_trancl) RS - ((result() RS eq_reflection) RS def_wfrec)); - -(*--------------------------------------------------------------------------- - * Old: - * val Term_rec_unfold = - * wf_pred_sexp RS wf_trancl RS (Term_rec_def RS def_wfrec); - *---------------------------------------------------------------------------*) - -(** conversion rules **) - -val [prem] = goal Term.thy - "N: list(term(A)) ==> \ -\ !M. (N,M): pred_sexp^+ --> \ -\ Abs_map (cut h (pred_sexp^+) M) N = \ -\ Abs_map h N"; -by (rtac (prem RS list.induct) 1); -by (Simp_tac 1); -by (strip_tac 1); -by (etac (pred_sexp_CONS_D RS conjE) 1); -by (asm_simp_tac (!simpset addsimps [trancl_pred_sexpD1]) 1); -qed "Abs_map_lemma"; - -val [prem1,prem2,A_subset_sexp] = goal Term.thy - "[| M: sexp; N: list(term(A)); A<=sexp |] ==> \ -\ Term_rec (M$N) d = d M N (Abs_map (%Z. Term_rec Z d) N)"; -by (rtac (Term_rec_unfold RS trans) 1); -by (simp_tac (HOL_ss addsimps - [Split, - prem2 RS Abs_map_lemma RS spec RS mp, pred_sexpI2 RS r_into_trancl, - prem1, prem2 RS rev_subsetD, list_subset_sexp, - term_subset_sexp, A_subset_sexp]) 1); -qed "Term_rec"; - -(*** term_rec -- by Term_rec ***) - -local - val Rep_map_type1 = read_instantiate_sg (sign_of Term.thy) - [("f","Rep_term")] Rep_map_type; - val Rep_Tlist = Rep_term RS Rep_map_type1; - val Rep_Term_rec = range_Leaf_subset_sexp RSN (2,Rep_Tlist RSN(2,Term_rec)); - - (*Now avoids conditional rewriting with the premise N: list(term(A)), - since A will be uninstantiated and will cause rewriting to fail. *) - val term_rec_ss = HOL_ss - addsimps [Rep_Tlist RS (rangeI RS term.APP_I RS Abs_term_inverse), - Rep_term_in_sexp, Rep_Term_rec, Rep_term_inverse, inj_Leaf, - inv_f_f, Abs_Rep_map, map_ident2, sexp.LeafI] -in - -val term_rec = prove_goalw Term.thy - [term_rec_def, App_def, Rep_Tlist_def, Abs_Tlist_def] - "term_rec (App f ts) d = d f ts (map (%t. term_rec t d) ts)" - (fn _ => [simp_tac term_rec_ss 1]) - -end; diff -r 1c0dfa7ebb72 -r 3f0ab2c306f7 src/HOL/ex/Term.thy --- a/src/HOL/ex/Term.thy Wed May 07 13:50:52 1997 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,55 +0,0 @@ -(* Title: HOL/ex/Term - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1992 University of Cambridge - -Terms over a given alphabet -- function applications; illustrates list functor - (essentially the same type as in Trees & Forests) - -There is no constructor APP because it is simply cons ($) -*) - -Term = SList + - -types 'a term - -arities term :: (term)term - -consts - term :: 'a item set => 'a item set - Rep_term :: 'a term => 'a item - Abs_term :: 'a item => 'a term - Rep_Tlist :: 'a term list => 'a item - Abs_Tlist :: 'a item => 'a term list - App :: ['a, ('a term)list] => 'a term - Term_rec :: ['a item, ['a item , 'a item, 'b list]=>'b] => 'b - term_rec :: ['a term, ['a ,'a term list, 'b list]=>'b] => 'b - -inductive "term(A)" - intrs - APP_I "[| M: A; N : list(term(A)) |] ==> M$N : term(A)" - monos "[list_mono]" - -defs - (*defining abstraction/representation functions for term list...*) - Rep_Tlist_def "Rep_Tlist == Rep_map(Rep_term)" - Abs_Tlist_def "Abs_Tlist == Abs_map(Abs_term)" - - (*defining the abstract constants*) - App_def "App a ts == Abs_term(Leaf(a) $ Rep_Tlist(ts))" - - (*list recursion*) - Term_rec_def - "Term_rec M d == wfrec (trancl pred_sexp) - (%g. Split(%x y. d x y (Abs_map g y))) M" - - term_rec_def - "term_rec t d == - Term_rec (Rep_term t) (%x y r. d (inv Leaf x) (Abs_Tlist(y)) r)" - -rules - (*faking a type definition for term...*) - Rep_term "Rep_term(n): term(range(Leaf))" - Rep_term_inverse "Abs_term(Rep_term(t)) = t" - Abs_term_inverse "M: term(range(Leaf)) ==> Rep_term(Abs_term(M)) = M" -end