src/ZF/Update.ML
changeset 5168 adafef6eb295
parent 5157 6e03de8ec2b4
child 6048 88e6e55dd168
equal deleted inserted replaced
5167:10e033194e9d 5168:adafef6eb295
    18 
    18 
    19 Goalw [update_def] "[| f`x = y;  f: Pi(A,B);  x: A |] ==> f(x:=y) = f";
    19 Goalw [update_def] "[| f`x = y;  f: Pi(A,B);  x: A |] ==> f(x:=y) = f";
    20 by (asm_simp_tac (simpset() addsimps [domain_of_fun, cons_absorb]) 1);
    20 by (asm_simp_tac (simpset() addsimps [domain_of_fun, cons_absorb]) 1);
    21 by (rtac fun_extension 1);
    21 by (rtac fun_extension 1);
    22 by (best_tac (claset() addIs [apply_type, if_type, lam_type]) 1);
    22 by (best_tac (claset() addIs [apply_type, if_type, lam_type]) 1);
    23 ba 1;
    23 by (assume_tac 1);
    24 by (Asm_simp_tac 1);
    24 by (Asm_simp_tac 1);
    25 qed "update_idem";
    25 qed "update_idem";
    26 
    26 
    27 
    27 
    28 (* [| f: Pi(A, B); x:A |] ==> f(x := f`x) = f *)
    28 (* [| f: Pi(A, B); x:A |] ==> f(x := f`x) = f *)