definition pre ≝ λS.\ 5a href="cic:/matita/tutorial/chapter4/pitem.ind(1,0,1)"\ 6pitem\ 5/a\ 6 S \ 5a title="Product" href="cic:/fakeuri.def(1)"\ 6×\ 5/a\ 6 \ 5a href="cic:/matita/basics/bool/bool.ind(1,0,0)" title="null"\ 6bool\ 5/a\ 6.
+definition test ≝ λS:Alpha.λe: pre S. match e with [mk_pair i b ⇒ e].
+
interpretation "pstar" 'kstar a = (pstar ? a).
interpretation "por" 'plus a b = (por ? a b).
interpretation "pcat" 'concat a b = (pconcat ? a b).