    # File lib/graphviz/attrs.rb, line 56
        def []=( xKey, xValue )
          unless @attributs.keys.include?( xKey.to_s )
            raise ArgumentError, "#{@name} attribut '#{xKey.to_s}' invalid"
          end

          @data[xKey.to_s] = GraphViz::Types.const_get(@attributs[xKey.to_s]).new( xValue )

          if @graphviz.nil? == false
            @graphviz.set_position( @name, xKey.to_s, @data[xKey.to_s] )
          end
        end