the support for reducibility candidates evolves ,,,,

[helm.git] / matita / matita / contribs / lambda_delta / Ground_2 / list.ma

diff --git a/matita/matita/contribs/lambda_delta/Ground_2/list.ma b/matita/matita/contribs/lambda_delta/Ground_2/list.ma
index 78a2305ea8dee7982f27c57203775de0911700af..09a52f57d4c8bb8bc6719cb1bfc2672d8dd8c037 100644 (file)
--- a/matita/matita/contribs/lambda_delta/Ground_2/list.ma
+++ b/matita/matita/contribs/lambda_delta/Ground_2/list.ma
@@ -37,3 +37,11 @@ inductive list2 (A1,A2:Type[0]) : Type[0] :=
 interpretation "nil (list of pairs)" 'Nil2 = (nil2 ? ?). (**) (* 'Nil causes unification error in aacr_abst *)
 
 interpretation "cons (list of pairs)" 'Cons hd1 hd2 tl = (cons2 ? ? hd1 hd2 tl).
+
+let rec append2 (A1,A2:Type[0]) (l1,l2:list2 A1 A2) on l1 ≝ match l1 with
+[ nil2           ⇒ l2
+| cons2 a1 a2 tl ⇒ {a1, a2} :: append2 A1 A2 tl l2
+].
+
+interpretation "append (list of pairs)"
+   'Append l1 l2 = (append2 ? ? l1 l2).