doc-src/TutorialI/Trie/Option2.thy
author wenzelm
Fri, 06 Oct 2000 17:35:58 +0200
changeset 10168 50be659d4222
parent 8771 026f37a86ea7
permissions -rw-r--r--
final tuning;

(*<*)
theory Option2 = Main:;
(*>*)

datatype 'a option = None | Some 'a;
(*<*)
end
(*>*)