# HG changeset patch
# User haftmann
# Date 1159822863 -7200
# Node ID f5f69a1059f458623d66034b0e4b45f7b1496ce3
# Parent  d4f94d2a3414b7c1b224f1fd139e6b0e62c62cf9
cleaned and extended

diff -r d4f94d2a3414 -r f5f69a1059f4 src/HOL/ex/NormalForm.thy
--- a/src/HOL/ex/NormalForm.thy	Mon Oct 02 23:01:00 2006 +0200
+++ b/src/HOL/ex/NormalForm.thy	Mon Oct 02 23:01:03 2006 +0200
@@ -16,63 +16,62 @@
 lemma "Suc n + Suc m = n + Suc (Suc m)" by normalization
 lemma "~((0::nat) < (0::nat))" by normalization
 
-
 datatype n = Z | S n
 consts
- add :: "n \<Rightarrow> n \<Rightarrow> n"
- add2 :: "n \<Rightarrow> n \<Rightarrow> n"
- mul :: "n \<Rightarrow> n \<Rightarrow> n"
- mul2 :: "n \<Rightarrow> n \<Rightarrow> n"
- exp :: "n \<Rightarrow> n \<Rightarrow> n"
+  add :: "n \<Rightarrow> n \<Rightarrow> n"
+  add2 :: "n \<Rightarrow> n \<Rightarrow> n"
+  mul :: "n \<Rightarrow> n \<Rightarrow> n"
+  mul2 :: "n \<Rightarrow> n \<Rightarrow> n"
+  exp :: "n \<Rightarrow> n \<Rightarrow> n"
 primrec
-"add Z = id"
-"add (S m) = S o add m"
+  "add Z = id"
+  "add (S m) = S o add m"
 primrec
-"add2 Z n = n"
-"add2 (S m) n = S(add2 m n)"
+  "add2 Z n = n"
+  "add2 (S m) n = S(add2 m n)"
 
 lemma [code]: "add2 (add2 n m) k = add2 n (add2 m k)"
-by(induct n) auto
-lemma [code]: "add2 n (S m) =  S(add2 n m)"
-by(induct n) auto
+  by(induct n) auto
+lemma [code]: "add2 n (S m) =  S (add2 n m)"
+  by(induct n) auto
 lemma [code]: "add2 n Z = n"
-by(induct n) auto
+  by(induct n) auto
 
 lemma "add2 (add2 n m) k = add2 n (add2 m k)" by normalization
 lemma "add2 (add2 (S n) (S m)) (S k) = S(S(S(add2 n (add2 m k))))" by normalization
 lemma "add2 (add2 (S n) (add2 (S m) Z)) (S k) = S(S(S(add2 n (add2 m k))))" by normalization
 
 primrec
-"mul Z = (%n. Z)"
-"mul (S m) = (%n. add (mul m n) n)"
+  "mul Z = (%n. Z)"
+  "mul (S m) = (%n. add (mul m n) n)"
 primrec
-"mul2 Z n = Z"
-"mul2 (S m) n = add2 n (mul2 m n)"
+  "mul2 Z n = Z"
+  "mul2 (S m) n = add2 n (mul2 m n)"
 primrec
-"exp m Z = S Z"
-"exp m (S n) = mul (exp m n) m"
+  "exp m Z = S Z"
+  "exp m (S n) = mul (exp m n) m"
 
 lemma "mul2 (S(S(S(S(S Z))))) (S(S(S Z))) = S(S(S(S(S(S(S(S(S(S(S(S(S(S(S Z))))))))))))))" by normalization
 lemma "mul (S(S(S(S(S Z))))) (S(S(S Z))) = S(S(S(S(S(S(S(S(S(S(S(S(S(S(S Z))))))))))))))" by normalization
 lemma "exp (S(S Z)) (S(S(S(S Z)))) = exp (S(S(S(S Z)))) (S(S Z))" by normalization
 
 lemma "(let ((x,y),(u,v)) = ((Z,Z),(Z,Z)) in add (add x y) (add u v)) = Z" by normalization
+lemma "split (%x y. x) (a, b) = a" by normalization
 lemma "(%((x,y),(u,v)). add (add x y) (add u v)) ((Z,Z),(Z,Z)) = Z" by normalization
 
 lemma "case Z of Z \<Rightarrow> True | S x \<Rightarrow> False" by normalization
 
-normal_form "[] @ []"
-normal_form "[] @ xs"
-normal_form "[a::'d,b,c] @ xs"
-normal_form "[%a::'x. a, %b. b, c] @ xs"
-normal_form "[%a::'x. a, %b. b, c] @ [u,v]"
-normal_form "map f (xs::'c list)"
-normal_form "map f [x,y,z::'x]"
+lemma "[] @ [] = []" by normalization
+lemma "[] @ xs = xs" by normalization
+lemma "[a \<Colon> 'd, b, c] @ xs = a # b # c # xs" by normalization
+lemma "[%a::'x. a, %b. b, c] @ xs = (%x. x) # (%x. x) # c # xs" by normalization
+lemma "[%a::'x. a, %b. b, c] @ [u,v] = [%x. x, %x. x, c, u, v]" by normalization
+lemma "map f [x,y,z::'x] = [f x, f y, f z]" by normalization
 normal_form "map (%f. f True) [id,g,Not]"
 normal_form "map (%f. f True) ([id,g,Not] @ fs)"
-normal_form "rev[a,b,c]"
+lemma "rev[a,b,c] = [c, b, a]" by normalization
 normal_form "rev(a#b#cs)"
-normal_form "map map [f,g,h]"
+lemma "map map [f,g,h] = [map f, map g, map h]" by normalization
 normal_form "map (%F. F [a,b,c::'x]) (map map [f,g,h])"
 normal_form "map (%F. F ([a,b,c] @ ds)) (map map ([f,g,h]@fs))"
 normal_form "map (%F. F [Z,S Z,S(S Z)]) (map map [S,add (S Z),mul (S(S Z)),id])"
@@ -86,28 +85,29 @@
 normal_form "filter (%x. x) ([True,False,x]@xs)"
 normal_form "filter Not ([True,False,x]@xs)"
 
-normal_form "[x,y,z] @ [a,b,c]"
+lemma "[x,y,z] @ [a,b,c] = [x, y, z, a, b ,c]" by normalization
 normal_form "%(xs, ys). xs @ ys"
 normal_form "(%(xs, ys). xs @ ys) ([a, b, c], [d, e, f])"
 normal_form "%x. case x of None \<Rightarrow> False | Some y \<Rightarrow> True"
 normal_form "map (%x. case x of None \<Rightarrow> False | Some y \<Rightarrow> True) [None, Some ()]"
 
-normal_form "last [a, b, c]"
-normal_form "last ([a, b, c] @ xs)"
+lemma "last [a, b, c] = c"
+  by normalization
+lemma "last ([a, b, c] @ xs) = (if null xs then c else last xs)"
+  by normalization
 
+lemma "(2::int) + 3 - 1 + (- k) * 2 = 4 + - k * 2" by normalization
+lemma "(-4::int) * 2 = -8" by normalization
+lemma "abs ((-4::int) + 2 * 1) = 2" by normalization
+lemma "(2::int) + 3 = 5" by normalization
+lemma "(2::int) + 3 * (- 4) * (- 1) = 14" by normalization
+lemma "(2::int) + 3 * (- 4) * 1 + 0 = -10" by normalization
+lemma "(2::int) < 3" by normalization
+lemma "(2::int) <= 3" by normalization
+lemma "abs ((-4::int) + 2 * 1) = 2" by normalization
+lemma "4 - 42 * abs (3 + (-7\<Colon>int)) = -164" by normalization
 normal_form "min 0 x"
 normal_form "min 0 (x::nat)"
-
-normal_form "(2::int) + 3 - 1 + (- k) * 2"
-normal_form "(4::int) * 2"
-normal_form "(-4::int) * 2"
-normal_form "abs ((-4::int) + 2 * 1)"
-normal_form "(2::int) + 3"
-normal_form "(2::int) + 3 * (- 4) * (- 1)"
-normal_form "(2::int) + 3 * (- 4) * 1 + 0"
-normal_form "(2::int) < 3"
-normal_form "(2::int) <= 3"
-normal_form "abs ((-4::int) + 2 * 1)"
-normal_form "4 - 42 * abs (3 + (-7\<Colon>int))"
+lemma "(if (0\<Colon>nat) \<le> (x\<Colon>nat) then 0\<Colon>nat else x) = 0" by normalization
 
 end