lab19: impl

lab19/tree.rb

@@ -5,6 +5,28 @@ class Tree
     @left = left
     @right = right
   end
+
+  def each_node(&block)
+    block.call(@value)
+    @left.each_node(&block) if @left
+    @right.each_node(&block) if @right
+  end
+
+  def method_missing(method_name, *args)
+    method_name = method_name.to_s
+    path = method_name.scan(/(left|right)/).flatten
+    current_node = self
+    path.each do |direction|
+      if direction == "left"
+        current_node = current_node.left
+      elsif direction == "right"
+        current_node = current_node.right
+      end
+      return nil if current_node.nil?
+    end
+    return current_node.value
+    super
+  end
 end
 
 my_tree = Tree.new(42,
@@ -32,4 +54,3 @@ p my_tree.left_left
 p my_tree.right_left
 p my_tree.left_left_right
 p my_tree.left_left_left_right
-