add (REXML::Document)

    # File temp/document.rb, line 69
                    def add( child )
                            if child.kind_of? XMLDecl
                                    @children.unshift child
                            elsif child.kind_of? DocType
            # Find first Element or DocType node and insert the decl right
            # before it.  If there is no such node, just insert the child at the
            # end.  If there is a child and it is an DocType, then replace it.
            insert_before_index = 0
            @children.find { |x|
              insert_before_index += 1
              x.kind_of?(Element) || x.kind_of?(DocType)
            }
            if @children[ insert_before_index ] # Not null = not end of list
              if @children[ insert_before_index ].kind_of DocType
                @children[ insert_before_index ] = child
              else
                @children[ index_before_index-1, 0 ] = child
              end
            else  # Insert at end of list
              @children[insert_before_index] = child
            end
                                    child.parent = self
                            else
                                    rv = super
                                    raise "attempted adding second root element to document" if @elements.size > 1
                                    rv
                            end
                    end