# File lib/graphviz.rb, line 690
  def self.default( hOpts )
    hOpts.each do |k, v|
      case k.to_s
        when "use"
          @@prog = v
        when "path"
          @@path = v.split( "," ).map{ |x| x.strip }
        when "errors"
          @@errors = v
        when "extlibs"
          @@extlibs = v.split( "," ).map{ |x| x.strip }
        when "output"
          warn ":output option is deprecated!"
          @@format = v
        else
          warn "Invalide option #{k}!"
      end
    end
  end