# File lib/puppet/external/dot.rb, line 308
308:     def to_s (t = '')
309:       t + "#{@from} #{edge_link} #{to} [\n" +
310:         @options.to_a.collect{ |i|
311:           i[1] && i[0] != 'label' ?
312:             t + $tab + "#{i[0]} = #{i[1]}" :
313:             i[1] ? t + $tab + "#{i[0]} = \"#{i[1]}\"" : nil
314:         }.compact.join( "\n" ) + "\n#{t}]\n"
315:     end