ruby tree ("seven languages")

tree1.rb

class Tree
  attr_accessor :children, :name

  def initialize(tree, name='root')
    @name = name
    @children = tree.map do |k,v|
      Tree.new(v, k)
    end
  end

  def visit_all(depth=0, &block)
    visit(depth, &block)
    children.each {|c| c.visit_all(depth+1, &block)}
  end

  def visit(depth=0, &block)
    block.call(self, depth)
  end
end

t = Tree.new({
               "Honor" => {
                 "America" => {
                   "Weapons" => {},
                   "Wood working" => {
                     "Haircuts" => {},
                     "Greatness Itself" => {}}},
                 "Buffets" => {
                   "Teamwork" => {},
                   "Selfishness" => {}}}})


t.visit_all do |node, depth|
  indent = '  ' * depth
  puts indent + node.name
end

The exercise was to extend the Tree class so you could pass a hash to the initialiser.