The "Ruby" way of doing an n-ary tree

I'm writing a Ruby script and would like to use a n-ary tree data structure.

Is there a good implementation that is available as source code? Thanks.

From stackoverflow

• A Hash whose attributes are all Arrays?

• To expand on Otto's answer, an easy way of getting a Hash to auto-vivify arrays is to use the default value block with Hash::new, like so:

  node_children = Hash.new { |_node_children, node_key| _node_children[node_key] = [] }
  

  But really, the code depends on what you want to do with your arrays. You can either set them up with Hashes and Arrays, or make some classes:

  class Node
      attr_accessor :value, :children
      def initialize(value, children=[])
       @value = value
       @children = children
      end
      def to_s(indent=0)
       value_s = @value.to_s
       sub_indent = indent + value_s.length
       value_s + @children.map { |child| " - " + child.to_s(sub_indent + 3) }.join("\n" + ' ' * sub_indent)
      end
  end
  
  ROOT = Node.new('root', %w{ farleft left center right farright }.map { |str| Node.new(str) } )
  puts "Original Tree"
  puts ROOT
  puts
  
  ROOT.children.each do |node| 
      node.children = %w{ one two three four }.map { |str| Node.new(node.value + ':' + str) }
  end
  puts "New Tree"
  puts ROOT
  puts
  

  This code, for example, gives:

  Original Tree
  root - farleft
       - left
       - center
       - right
       - farright
  
  New Tree
  root - farleft - farleft:one
                 - farleft:two
                 - farleft:three
                 - farleft:four
       - left - left:one
              - left:two
              - left:three
              - left:four
       - center - center:one
                - center:two
                - center:three
                - center:four
       - right - right:one
               - right:two
               - right:three
               - right:four
       - farright - farright:one
                  - farright:two
                  - farright:three
                  - farright:four
  

• The RubyTree gem worked great for me.