def handle(text)
      text.gsub!(/^([ \t#]*):(\w+):\s*(.+)?\n/) do 
        prefix    = $1
        directive = $2.downcase
        param     = $3

        case directive
        when "include"
          filename = param.split[0]
          include_file(filename, prefix)

        else
          yield(directive, param)
        end
      end
    end
def handle(text)
      text.gsub!(/^([ \t#]*):(\w+):\s*(.+)?\n/) do 
        prefix    = $1
        directive = $2.downcase
        param     = $3

        case directive
        when "include"
          filename = param.split[0]
          include_file(filename, prefix)

        else
          yield(directive, param)
        end
      end
    end
Look for common options in a chunk of text. Options that
 we don't handle are passed back to our caller
 as |directive, param|