X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;ds=sidebyside;f=helm%2Fsoftware%2Fmatita%2Flibrary%2Fdatatypes%2Fconstructors.ma;h=dd2a1760b9c640c7853fafbeb33babe2d7670ad2;hb=7782637e13656ec7d1d0ccc84e0d8cf894431187;hp=3567dd915463c8b6c2f809ed8218987a67e78042;hpb=437246a8e84268383a2f53f76442d811af3e8056;p=helm.git

diff --git a/helm/software/matita/library/datatypes/constructors.ma b/helm/software/matita/library/datatypes/constructors.ma
index 3567dd915..dd2a1760b 100644
--- a/helm/software/matita/library/datatypes/constructors.ma
+++ b/helm/software/matita/library/datatypes/constructors.ma
@@ -17,7 +17,9 @@ include "logic/equality.ma".
 
 inductive void : Set \def.
 
-inductive Prod (A,B:Set) : Set \def
+inductive unit : Set ≝ something: unit.
+
+inductive Prod (A,B:Type) : Type \def
 pair : A \to B \to Prod A B.
 
 interpretation "Pair construction" 'pair x y =
@@ -32,11 +34,11 @@ interpretation "Product" 'product x y =
 notation "hvbox(x break \times y)" with precedence 89
 for @{ 'product $x $y}.
 
-definition fst \def \lambda A,B:Set.\lambda p: Prod A B.
+definition fst \def \lambda A,B:Type.\lambda p: Prod A B.
 match p with
 [(pair a b) \Rightarrow a]. 
 
-definition snd \def \lambda A,B:Set.\lambda p: Prod A B.
+definition snd \def \lambda A,B:Type.\lambda p: Prod A B.
 match p with
 [(pair a b) \Rightarrow b].
 
@@ -52,22 +54,18 @@ interpretation "Second projection" 'snd x =
 notation "\snd x" with precedence 89
 for @{ 'snd $x}.
 
-theorem eq_pair_fst_snd: \forall A,B:Set.\forall p:Prod A B.
+theorem eq_pair_fst_snd: \forall A,B:Type.\forall p:Prod A B.
 p = 〈 (\fst p), (\snd p) 〉.
 intros.elim p.simplify.reflexivity.
 qed.
 
-inductive Sum (A,B:Set) : Set \def
+inductive Sum (A,B:Type) : Type \def
   inl : A \to Sum A B
 | inr : B \to Sum A B.
 
-inductive ProdT (A,B:Type) : Type \def
-pairT : A \to B \to ProdT A B.
-
-definition fstT \def \lambda A,B:Type.\lambda p: ProdT A B.
-match p with
-[(pairT a b) \Rightarrow a]. 
+interpretation "Disjoint union" 'plus A B =
+ (cic:/matita/datatypes/constructors/Sum.ind#xpointer(1/1) A B).
 
-definition sndT \def \lambda A,B:Type.\lambda p: ProdT A B.
-match p with
-[(pairT a b) \Rightarrow b].
\ No newline at end of file
+inductive option (A:Type) : Type ≝
+   None : option A
+ | Some : A → option A.
\ No newline at end of file