--- a/src/ZF/ex/contract0.ML Sat Apr 05 16:18:58 2003 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,117 +0,0 @@
-(* Title: ZF/ex/contract.ML
- ID: $Id$
- Author: Lawrence C Paulson
- Copyright 1993 University of Cambridge
-
-For ex/contract.thy.
-*)
-
-open Contract0;
-
-structure Contract = Inductive_Fun
- (val thy = Contract0.thy;
- val rec_doms = [("contract","comb*comb")];
- val sintrs =
- ["[| p:comb; q:comb |] ==> K#p#q -1-> p",
- "[| p:comb; q:comb; r:comb |] ==> S#p#q#r -1-> (p#r)#(q#r)",
- "[| p-1->q; r:comb |] ==> p#r -1-> q#r",
- "[| p-1->q; r:comb |] ==> r#p -1-> r#q"];
- val monos = [];
- val con_defs = [];
- val type_intrs = Comb.intrs@[SigmaI];
- val type_elims = [SigmaE2]);
-
-val [K_contract,S_contract,Ap_contract1,Ap_contract2] = Contract.intrs;
-
-val contract_induct = standard
- (Contract.mutual_induct RS spec RS spec RSN (2,rev_mp));
-
-(*For type checking: replaces a-1->b by a,b:comb *)
-val contract_combE2 = Contract.dom_subset RS subsetD RS SigmaE2;
-val contract_combD1 = Contract.dom_subset RS subsetD RS SigmaD1;
-val contract_combD2 = Contract.dom_subset RS subsetD RS SigmaD2;
-
-goal Contract.thy "field(contract) = comb";
-by (fast_tac (ZF_cs addIs [equalityI,K_contract] addSEs [contract_combE2]) 1);
-val field_contract_eq = result();
-
-val reduction_refl = standard
- (field_contract_eq RS equalityD2 RS subsetD RS rtrancl_refl);
-
-val rtrancl_into_rtrancl2 = standard
- (r_into_rtrancl RS (trans_rtrancl RS transD));
-
-val reduction_rls = [reduction_refl, K_contract, S_contract,
- K_contract RS rtrancl_into_rtrancl2,
- S_contract RS rtrancl_into_rtrancl2,
- Ap_contract1 RS rtrancl_into_rtrancl2,
- Ap_contract2 RS rtrancl_into_rtrancl2];
-
-goalw Contract.thy [I_def] "!!p. p:comb ==> I#p ---> p";
-by (REPEAT (ares_tac (Comb.intrs @ reduction_rls) 1));
-val I_reduce = result();
-
-goalw Contract.thy [I_def] "I: comb";
-by (REPEAT (ares_tac Comb.intrs 1));
-val I_comb = result();
-
-(** Non-contraction results **)
-
-(*Derive a case for each combinator constructor*)
-val K_contract_case = Contract.mk_cases Comb.con_defs "K -1-> r";
-val S_contract_case = Contract.mk_cases Comb.con_defs "S -1-> r";
-val Ap_contract_case = Contract.mk_cases Comb.con_defs "p#q -1-> r";
-
-val contract_cs =
- ZF_cs addSIs Comb.intrs
- addIs Contract.intrs
- addSEs [contract_combD1,contract_combD2] (*type checking*)
- addSEs [K_contract_case, S_contract_case, Ap_contract_case]
- addSEs Comb.free_SEs;
-
-goalw Contract.thy [I_def] "!!r. I -1-> r ==> P";
-by (fast_tac contract_cs 1);
-val I_contract_case = result();
-
-goal Contract.thy "!!p r. K#p -1-> r ==> (EX q. r = K#q & p -1-> q)";
-by (fast_tac contract_cs 1);
-val K1_contractD = result();
-
-goal Contract.thy "!!p r. [| p ---> q; r: comb |] ==> p#r ---> q#r";
-by (forward_tac [rtrancl_type RS subsetD RS SigmaD1] 1);
-by (dtac (field_contract_eq RS equalityD1 RS subsetD) 1);
-by (etac rtrancl_induct 1);
-by (fast_tac (contract_cs addIs reduction_rls) 1);
-by (etac (trans_rtrancl RS transD) 1);
-by (fast_tac (contract_cs addIs reduction_rls) 1);
-val Ap_reduce1 = result();
-
-goal Contract.thy "!!p r. [| p ---> q; r: comb |] ==> r#p ---> r#q";
-by (forward_tac [rtrancl_type RS subsetD RS SigmaD1] 1);
-by (dtac (field_contract_eq RS equalityD1 RS subsetD) 1);
-by (etac rtrancl_induct 1);
-by (fast_tac (contract_cs addIs reduction_rls) 1);
-by (etac (trans_rtrancl RS transD) 1);
-by (fast_tac (contract_cs addIs reduction_rls) 1);
-val Ap_reduce2 = result();
-
-(** Counterexample to the diamond property for -1-> **)
-
-goal Contract.thy "K#I#(I#I) -1-> I";
-by (REPEAT (ares_tac [K_contract, I_comb, Ap_comb] 1));
-val KIII_contract1 = result();
-
-goalw Contract.thy [I_def] "K#I#(I#I) -1-> K#I#((K#I)#(K#I))";
-by (DEPTH_SOLVE (resolve_tac (Comb.intrs @ Contract.intrs) 1));
-val KIII_contract2 = result();
-
-goal Contract.thy "K#I#((K#I)#(K#I)) -1-> I";
-by (REPEAT (ares_tac (Comb.intrs @ [K_contract, I_comb]) 1));
-val KIII_contract3 = result();
-
-goalw Contract.thy [diamond_def] "~ diamond(contract)";
-by (fast_tac (ZF_cs addIs [KIII_contract1,KIII_contract2,KIII_contract3]
- addSEs [I_contract_case]) 1);
-val not_diamond_contract = result();
-
-writeln"Reached end of file.";