# File lib/sass/scss/rx.rb, line 13
      def self.escape_ident(str)
        return "" if str.empty?
        return "\\#{str}" if str == '-' || str == '_'
        out = ""
        value = str.dup
        out << value.slice!(0...1) if value =~ /^[-_]/
        if value[0...1] =~ NMSTART
          out << value.slice!(0...1)
        else
          out << escape_char(value.slice!(0...1))
        end
        out << value.gsub(/[^a-zA-Z0-9_-]/) {|c| escape_char c}
        return out
      end