src/Doc/Prog_Prove/MyList.thy
author wenzelm
Tue, 31 Jan 2023 17:17:07 +0100
changeset 77152 4c9296390f20
parent 57804 fcf966675478
permissions -rw-r--r--
more accurate output: avoid output_main from last run;

theory MyList
imports Main
begin

datatype 'a list = Nil | Cons 'a "'a list"

fun app :: "'a list => 'a list => 'a list" where
"app Nil ys = ys" |
"app (Cons x xs) ys = Cons x (app xs ys)"

fun rev :: "'a list => 'a list" where
"rev Nil = Nil" |
"rev (Cons x xs) = app (rev xs) (Cons x Nil)"

value "rev(Cons True (Cons False Nil))"

(* a comment *)

end