Whats the significance of return by reference?

Question

In C++,

function() = 10;

works if the function returns a variable by reference.

What are the use cases of it?

Answer 1

A very normal use case is when you write an array like class. Here you want to overload the operator [] so as you can do a[0] = 10; In that case you would want the signature to be like int& operator[](int index);