Prototype in Python3

Question

Hi!
How can I add functions to an existing class? I want to recreate something like this: (JS)
String.prototype.red = () => {...}
How can I add a method to the str class?

Answer 1

Python inheritance model is class based not prototype based like JavaScript. So your question should be how you can extend a data class in Python. The answer to that is INHERITANCE.

class A (B):
# A extends B

It is more tricky with str because str is not a Python type. It is implemented in C. It is a special case constructor.

Your best bet is composition. You may store the str object as a hidden field(double underscores) for your new data type and indirectly work with it.

Answer 2

Ore Thank you