src/Doc/Tutorial/Misc/fakenat.thy
author wenzelm
Sat, 01 Jun 2019 11:29:59 +0200
changeset 70299 83774d669b51
parent 67406 23307fd33906
child 80914 d97fdabd9e2b
permissions -rw-r--r--
Added tag Isabelle2019-RC4 for changeset ad2d84c42380

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

text\<open>\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:
\<close>

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