add_converter

# File lib/csv/fields_converter.rb, line 17
    def add_converter(name=nil, &converter)
      if name.nil?  # custom converter
        @converters << converter
      else          # named converter
        combo = @builtin_converters[name]
        case combo
        when Array  # combo converter
          combo.each do |sub_name|
            add_converter(sub_name)
          end
        else        # individual named converter
          @converters << combo
        end
      end
    end