tasks a-s

Task/Parametric-polymorphism/Perl-6/parametric-polymorphism.pl6

@@ -0,0 +1,20 @@
+role BinaryTree[::T] {
+    has T $!value;
+    has BinaryTree[T] $.left;
+    has BinaryTree[T] $.right;
+
+    method replace-all(T $value) {
+        $!value = $value;
+        $.left.?replace-all($value);
+        $.right.?replace-all($value);
+    }
+}
+
+class IntTree does BinaryTree[Int] { }
+
+my IntTree $it .= new(value => 1,
+                      left  => IntTree.new(value => 2),
+                      right => IntTree.new(value => 3));
+
+$it.replace-all(42);
+say $it.perl;