# File rlml.rb, line 413
    def encoding(e = 'utf-8')
      if e =~ /[\w_-]+/
        @output << "rlml/#{e}"
        @encoding = e
        @just_after_header = true
      else
        raise WriteError, "Invalid encoding: #{e}"
      end
      @header_emitted = true
      self
    end