1.1 --- a/doc-src/Intro/advanced.tex Mon Jul 11 17:50:34 1994 +0200
1.2 +++ b/doc-src/Intro/advanced.tex Mon Jul 11 18:26:57 1994 +0200
1.3 @@ -864,14 +864,14 @@
1.4 \begin{ttbox}
1.5 goal Nat.thy "~ (Suc(k) = k)";
1.6 {\out Level 0}
1.7 -{\out ~Suc(k) = k}
1.8 -{\out 1. ~Suc(k) = k}
1.9 +{\out Suc(k) ~= k}
1.10 +{\out 1. Suc(k) ~= k}
1.11 \ttbreak
1.12 by (res_inst_tac [("n","k")] induct 1);
1.13 {\out Level 1}
1.14 -{\out ~Suc(k) = k}
1.15 -{\out 1. ~Suc(0) = 0}
1.16 -{\out 2. !!x. ~Suc(x) = x ==> ~Suc(Suc(x)) = Suc(x)}
1.17 +{\out Suc(k) ~= k}
1.18 +{\out 1. Suc(0) ~= 0}
1.19 +{\out 2. !!x. Suc(x) ~= x ==> Suc(Suc(x)) ~= Suc(x)}
1.20 \end{ttbox}
1.21 We should check that Isabelle has correctly applied induction. Subgoal~1
1.22 is the base case, with $k$ replaced by~0. Subgoal~2 is the inductive step,
1.23 @@ -881,14 +881,14 @@
1.24 \begin{ttbox}
1.25 by (resolve_tac [notI] 1);
1.26 {\out Level 2}
1.27 -{\out ~Suc(k) = k}
1.28 +{\out Suc(k) ~= k}
1.29 {\out 1. Suc(0) = 0 ==> False}
1.30 -{\out 2. !!x. ~Suc(x) = x ==> ~Suc(Suc(x)) = Suc(x)}
1.31 +{\out 2. !!x. Suc(x) ~= x ==> Suc(Suc(x)) ~= Suc(x)}
1.32 \ttbreak
1.33 by (eresolve_tac [Suc_neq_0] 1);
1.34 {\out Level 3}
1.35 -{\out ~Suc(k) = k}
1.36 -{\out 1. !!x. ~Suc(x) = x ==> ~Suc(Suc(x)) = Suc(x)}
1.37 +{\out Suc(k) ~= k}
1.38 +{\out 1. !!x. Suc(x) ~= x ==> Suc(Suc(x)) ~= Suc(x)}
1.39 \end{ttbox}
1.40 The inductive step holds by the contrapositive of~\ttindex{Suc_inject}.
1.41 Negation rules transform the subgoal into that of proving $Suc(x)=x$ from
1.42 @@ -896,17 +896,17 @@
1.43 \begin{ttbox}
1.44 by (resolve_tac [notI] 1);
1.45 {\out Level 4}
1.46 -{\out ~Suc(k) = k}
1.47 -{\out 1. !!x. [| ~Suc(x) = x; Suc(Suc(x)) = Suc(x) |] ==> False}
1.48 +{\out Suc(k) ~= k}
1.49 +{\out 1. !!x. [| Suc(x) ~= x; Suc(Suc(x)) = Suc(x) |] ==> False}
1.50 \ttbreak
1.51 by (eresolve_tac [notE] 1);
1.52 {\out Level 5}
1.53 -{\out ~Suc(k) = k}
1.54 +{\out Suc(k) ~= k}
1.55 {\out 1. !!x. Suc(Suc(x)) = Suc(x) ==> Suc(x) = x}
1.56 \ttbreak
1.57 by (eresolve_tac [Suc_inject] 1);
1.58 {\out Level 6}
1.59 -{\out ~Suc(k) = k}
1.60 +{\out Suc(k) ~= k}
1.61 {\out No subgoals!}
1.62 \end{ttbox}
1.63
1.64 @@ -983,7 +983,7 @@
1.65 insert the equations proved in the previous section, namely
1.66 $0+n=n$ and ${\tt Suc}(m)+n={\tt Suc}(m+n)$:
1.67 \begin{ttbox}
1.68 -val add_ss = FOL_ss addrews [add_0, add_Suc];
1.69 +val add_ss = FOL_ss addsimps [add_0, add_Suc];
1.70 \end{ttbox}
1.71 We state the goal for associativity of addition, and
1.72 use \ttindex{res_inst_tac} to invoke induction on~$k$: