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--- at:tutorial:objects [2007/06/29 09:08] – jorge
+++ at:tutorial:objects [2007/06/29 11:01] – jorge
@@ Line 52: / Line 52: @@
 ===== Delegation and Dynamic Inheritance =====
-AmbientTalk features object inheritance or delegation. Through delegation an object can rely upon another to provide a specified set of functionalities. We identify two different relationships between objects that
+AmbientTalk features object inheritance or delegation. By means of delegation, an object can reuse and extend the defintion of another establishing a child-parent relationship. We identify two kinds of delegation relationships: **IS-A** and **SHARE-A**, embodied by the ''extend: with:'' and ''share: with:'' language constructs respectively.
+The following code shows how to extend objects with a **IS-A** relationship.
+<code>
+> def point3D := extend: point with: {
+    def z := 0;
+    def sumofsquares() {
+      super.sumofsquares() + z*z
+    }
+  }
+>><object:13393337>
+</code>
+The following code shows how to extend objects with a **SHARE-A** relationship.
+<code>
+> def point3D := share: point with: {
+    def z := 0;
+    def sumofsquares() {
+      super.sumofsquares() + z*z
+    }
+  }
+>><object:13323337>
+</code>
+These relationships defines two different semantics for clonning child objects
+ in the way
+. While both relationships
+ Extending an object with a **is-a** relationship
 ===== Delegation and cloning =====