# File lib/multi_json/vendor/ok_json.rb, line 487
    def hexenc4(t, u)
      t.putc(Hex[(u>>12)&0xf])
      t.putc(Hex[(u>>8)&0xf])
      t.putc(Hex[(u>>4)&0xf])
      t.putc(Hex[u&0xf])
    end