Compatibility with PHP 5.6

This package was made with PHP 7 in mind, because of its speed and ease of use now that scalar type hinting is included within the language itself.

That being said, it is a LOT of coding to actually go back to PHP 5.6, however, you could use the Transphpile library to compile your own PHP 5.6 version of this library. It's however not guaranteed to work and always remember that PHP7 is faster (a lot faster!) than PHP 5.6, and if there is one thing that Telegram likes... is fast bots!