class Sass::Engine

def parse_attribute(line, attribute_regx)
  if @options[:attribute_syntax] == :normal &&
      attribute_regx == ATTRIBUTE_ALTERNATE
    raise SyntaxError.new("Illegal attribute syntax: can't use alternate syntax when :attribute_syntax => :normal is set.")
  elsif @options[:attribute_syntax] == :alternate &&
      attribute_regx == ATTRIBUTE
    raise SyntaxError.new("Illegal attribute syntax: can't use normal syntax when :attribute_syntax => :alternate is set.")
  end
  name, eq, value = line.scan(attribute_regx)[0]
  if name.nil? || value.nil?
    raise SyntaxError.new("Invalid attribute: \"#{line}\".", @line)
  end
  if eq.strip[0] == SCRIPT_CHAR
    value = Sass::Constant.parse(value, @constants, @line).to_s
  end
  Tree::AttrNode.new(name, value, @options[:style])
end