overload_arithmetic.md

Overloading Arithmetic Operators

Arithmetic operators like + perform an arithmetic operation without modifying their operands, and return the result by value.

Example

struct point {
    int x, y;
    // implementation as member function
    point operator+(point other) const {
        return {x + other.x, y + other.y};
    }
};
// better: free function (can be hidden friend)
point operator-(point a, point b) {
    return {a.x - b.x, a.y - b.y};
}
// implement using *= (if it exists)
point operator*(point a, point b) {
    return a *= b;
}

Note: for large types, pass as const& and not by value