include methods from external php file in a class

Question

I have a class with own methods and on the other side a php file what contains external methods. From documentation is clear that inside of a class includeing external functions is not possible

How could I inculde this functions in my class. Making an another class and extend my first class it can not be an option.

Answer 1

You can't. All class definition, including methods and fields must be on the same file. You can't declare the same class in two different files.

Extending, or using traits (if you have PHP 5.4.x+), are your only options.