vec2: float& operator[](size_t index)

Return a reference to x if index is 0 or a reference to y if index is 1, else, throw an exception.

Example

#include "include/vec2.h"
#include <iostream>

int main() {
        nml::vec2 v(1.0f, 2.0f);
        v[0] = 3.0f;
        v[1] = 1.0f;
        std::cout << nml::to_string(v) << std::endl;
        v[2] = 2.0; // Error

        return 0;
}

Result:

[3.000000, 1.000000]
terminate called after throwing an instance of 'std::out_of_range'
        what():  vec2::operator[]: index is out of range.
Aborted