def constants(opts = {})
      opts = SymbolHash[:included => true].update(opts)
      consts = children.select {|o| o.is_a? ConstantObject }
      consts + (opts[:included] ? included_constants : [])
    end
def constants(opts = {})
      opts = SymbolHash[:included => true].update(opts)
      consts = children.select {|o| o.is_a? ConstantObject }
      consts + (opts[:included] ? included_constants : [])
    end
Returns all constants in the namespace

 @option opts [Boolean] :included (true) whether or not to include
   mixed in constants in list
 @return [Array<ConstantObject>] a list of constant objects