Operator Overloading

// Operator overloading goes against V's philosophy of simplicity and predictability.
// But since scientific and graphical applications are among V's domains, operator overloading is very important to have in order to improve readability:
// a.add(b).add(c.mul(d)) is a lot less readable than a + b + c * d.

// To improve safety and maintainability, operator overloading has several limitations:

// - It's only possible to overload +, -, *, / operators.
// - Calling other functions inside operator functions is not allowed.
// - Operator functions can't modify their arguments.
// - Both arguments must have the same type (just like with all operators in V).

struct Vec {
	x int
	y int
}

fn (a Vec) str() string {
	return '{$a.x, $a.y}'
}

fn (a Vec) + (b Vec) Vec {
	return Vec {
		a.x + b.x,
		a.y + b.y
	}
}

fn (a Vec) - (b Vec) Vec {
	return Vec {
		a.x - b.x,
		a.y - b.y
	}
}

fn main() {
	a := Vec{2, 3}
	b := Vec{4, 5}
	println(a + b) // "{6, 8}" 
	println(a - b) // "{-2, -2}" 
}