1 > goal Nat.thy "(k+m)+n = k+(m+n)";
3 k + m + n = k + (m + n)
4 1. k + m + n = k + (m + n)
6 > by (resolve_tac [induct] 1);
8 k + m + n = k + (m + n)
10 2. !!x. k + m + n = x ==> k + m + n = Suc(x)
14 k + m + n = k + (m + n)
16 2. !!x. k + m + n = k + x ==> k + m + n = k + Suc(x)
20 k + m + n = k + (m + n)
21 1. k + m + 0 = k + (m + 0)
22 2. !!x. k + m + x = k + (m + x) ==> k + m + Suc(x) = k + (m + Suc(x))
26 k + m + n = k + (m + n)
27 1. k + m + n = k + (m + 0)
28 2. !!x. k + m + n = k + (m + x) ==> k + m + n = k + (m + Suc(x))
31 > val nat_congs = prths (mk_congs Nat.thy ["Suc", "op +"]);
32 ?Xa = ?Ya ==> Suc(?Xa) = Suc(?Ya)
34 [| ?Xa = ?Ya; ?Xb = ?Yb |] ==> ?Xa + ?Xb = ?Ya + ?Yb
36 ?Xa = ?Ya ==> Suc(?Xa) = Suc(?Ya)
37 [| ?Xa = ?Ya; ?Xb = ?Yb |] ==> ?Xa + ?Xb = ?Ya + ?Yb
38 val nat_congs = [, ] : thm list
39 > val add_ss = FOL_ss addcongs nat_congs
40 # addrews [add_0, add_Suc];
41 val add_ss = ? : simpset
42 > goal Nat.thy "(k+m)+n = k+(m+n)";
44 k + m + n = k + (m + n)
45 1. k + m + n = k + (m + n)
46 val it = [] : thm list
47 > by (res_inst_tac [("n","k")] induct 1);
49 k + m + n = k + (m + n)
50 1. 0 + m + n = 0 + (m + n)
51 2. !!x. x + m + n = x + (m + n) ==> Suc(x) + m + n = Suc(x) + (m + n)
53 > by (SIMP_TAC add_ss 1);
55 k + m + n = k + (m + n)
56 1. !!x. x + m + n = x + (m + n) ==> Suc(x) + m + n = Suc(x) + (m + n)
58 > by (ASM_SIMP_TAC add_ss 1);
60 k + m + n = k + (m + n)
63 > val add_assoc = result();
64 ?k + ?m + ?n = ?k + (?m + ?n)