doc-src/TutorialI/ToyList2/ToyList2
author huffman
Wed, 10 Aug 2011 08:42:26 -0700
changeset 44132 0f35a870ecf1
parent 10171 59d6633835fa
permissions -rw-r--r--
full import paths

lemma app_Nil2 [simp]: "xs @ [] = xs"
apply(induct_tac xs)
apply(auto)
done

lemma app_assoc [simp]: "(xs @ ys) @ zs = xs @ (ys @ zs)"
apply(induct_tac xs)
apply(auto)
done

lemma rev_app [simp]: "rev(xs @ ys) = (rev ys) @ (rev xs)"
apply(induct_tac xs)
apply(auto)
done

theorem rev_rev [simp]: "rev(rev xs) = xs"
apply(induct_tac xs)
apply(auto)
done

end