# File dot/dot.rb, line 237
237:         def initialize( params = {}, option_list = EDGE_OPTS )
238:             super( params, option_list )
239:             @from = params['from'] ? params['from'] : nil
240:             @to = params['to'] ? params['to'] : nil
241:         end

     # File dot/dot.rb, line 243
243:         def to_s( t = '' )
244:             t + "#{@from} -> #{to} [\n" +
245:             @options.to_a.collect{ |i|
246:                 i[1] && i[0] != 'label' ?
247:                     t + $tab + "#{i[0]} = #{i[1]}" :
248:                     i[1] ? t + $tab + "#{i[0]} = \"#{i[1]}\"" : nil
249:             }.compact.join( "\n" ) + "\n" + t + "]\n"
250:         end