module RuboCop::AST::Traversal

def on_class(node)
  children = node.children
  child = children[0] # always const???
  send(:"on_#{child.type}", child)
  if (child = children[1])
    send(:"on_#{child.type}", child)
  end
  return unless (child = children[2])
  send(:"on_#{child.type}", child)
end