Initial data commit

Task/Delegates/Elena/delegates-1.elena

@@ -0,0 +1,46 @@
+import extensions;
+import system'routines;
+
+interface IOperable
+{
+    abstract operate() {}
+}
+
+class Operable : IOperable
+{
+    constructor() {}
+
+    operate()
+        = "delegate implementation";
+}
+
+class Delegator
+{
+    object theDelegate;
+
+    set Delegate(object)
+    {
+        theDelegate := object
+    }
+
+    internal operate(operable)
+        = "default implementation";
+
+    internal operate(IOperable operable)
+        = operable.operate();
+
+    operate()
+        <= operate(theDelegate);
+}
+
+public program()
+{
+    var delegator := new Delegator();
+
+    new object[]{nil, new Object(), new Operable()}.forEach:(o)
+    {
+       delegator.Delegate := o;
+
+       console.printLine(delegator.operate())
+    }
+}

Task/Delegates/Elena/delegates-2.elena

@@ -0,0 +1,47 @@
+import extensions;
+import system'routines;
+
+class Operable
+{
+    Operable = self;
+
+    operate()
+        = "delegate implementation";
+}
+
+class Delegator
+{
+    prop object Delegate;
+
+    constructor()
+    {
+        Delegate := nil
+    }
+
+    operate()
+    {
+        // if the object does not support "get&operable" message - returns nil
+        var operable := Delegate.Operable \ back:nil;
+
+        if (nil == operable)
+        {
+            ^ "default implementation"
+        }
+        else
+        {
+            ^ operable.operate()
+        }
+    }
+}
+
+public program()
+{
+    var delegator := new Delegator();
+
+    new object[]{nil, new Object(), new Operable()}.forEach:(o)
+    {
+       delegator.Delegate := o;
+
+       console.printLine(delegator.operate())
+    }
+}