Added datatypes/constructors.ma

diff --git a/helm/matita/library/datatypes/constructors.ma b/helm/matita/library/datatypes/constructors.ma
new file mode 100644 (file)
index 0000000..c2bdc56
--- /dev/null
+++ b/helm/matita/library/datatypes/constructors.ma
@@ -0,0 +1,24 @@
+(**************************************************************************)
+(*       ___                                                               *)
+(*      ||M||                                                             *)
+(*      ||A||       A project by Andrea Asperti                           *)
+(*      ||T||                                                             *)
+(*      ||I||       Developers:                                           *)
+(*      ||T||       A.Asperti, C.Sacerdoti Coen,                          *)
+(*      ||A||       E.Tassi, S.Zacchiroli                                 *)
+(*      \   /                                                             *)
+(*       \ /        This file is distributed under the terms of the       *)
+(*        v         GNU Lesser General Public License Version 2.1         *)
+(*                                                                        *)
+(**************************************************************************)
+
+set "baseuri" "cic:/matita/datatypes/constructors/".
+
+inductive void : Set \def.
+
+inductive Prod (A,B:Set) : Set \def
+pair : A \to B \to Prod A B.
+
+inductive Sum (A,B:Set) : Set \def
+  inl : A \to Sum A B
+| inr : B \to Sum A B.
\ No newline at end of file