new (REXML::IOSource)

    # File temp/source.rb, line 127
                    def initialize(arg, block_size=500)
                            @er_source = @source = arg
                            @to_utf = false
          # Determining the encoding is a deceptively difficult issue to resolve.
          # First, we check the first two bytes for UTF-16.  Then we
          # assume that the encoding is at least ASCII enough for the '>', and
          # we read until we get one of those.  This gives us the XML declaration,
          # if there is one.  If there isn't one, the file MUST be UTF-8, as per
          # the XML spec.  If there is one, we can determine the encoding from
          # it.
          str = @source.read( 2 )
          if (str[0] == 254 && str[1] == 255) || (str[0] == 255 && str[1] == 254)
            @encoding = check_encoding( str )
            @line_break = encode( '>' )
          else
            @line_break = '>'
          end
          super str+@source.readline( @line_break )
                    end