def inspect
str = "<##{self.class} io_type:"
if @io == $stdout then str << "$stdout"
elsif @io == $stdin then str << "$stdin"
elsif @io == $stderr then str << "$stderr"
else str << @io.class.to_s
end
if @io.respond_to?(:path) and (p = @io.path)
str << " io_path:#{p.inspect}"
end
%w[ lineno col_sep row_sep
quote_char skip_blanks encoding ].each do |attr_name|
if a = instance_variable_get("@#{attr_name}")
str << " #{attr_name}:#{a.inspect}"
end
end
if @use_headers
str << " headers:#{(@headers || true).inspect}"
end
str << ">"
end