src/Doc/Tutorial/Misc/fakenat.thy
author wenzelm
Tue, 17 Jan 2017 16:11:47 +0100
changeset 64917 5db5b8cf6dc6
parent 58860 fee7cfa69c50
child 67406 23307fd33906
permissions -rw-r--r--
removed some old ASCII syntax;

(*<*)
theory fakenat imports Main begin
(*>*)

text{*\noindent
The type \tydx{nat} of natural
numbers is predefined to have the constructors \cdx{0} and~\cdx{Suc}.
It behaves approximately as if it were declared like this:
*}

datatype nat = zero ("0") | Suc nat
(*<*)
end
(*>*)