def method_missing(meth, *args, &block)
      if @node.respond_to?(meth)
        @node.send meth, *args, &block
      elsif @node.children.respond_to?(meth)
        @node.children.send meth, *args, &block
      else
        super
      end
    end
def method_missing(meth, *args, &block)
      if @node.respond_to?(meth)
        @node.send meth, *args, &block
      elsif @node.children.respond_to?(meth)
        @node.children.send meth, *args, &block
      else
        super
      end
    end
Initialize

 @param node [Parser::AST::Node] args node.
 If args node responds method itself, call method on args node.
 If args children (array) responds method,  call method on args children.
 Otherwise raise method missing error.