Pragmatic Scala

Operator Overloading

Technically, Scala has no operators, so operator overloading means overloading symbols like +, +-, and so on. In Scala, these are method names. Operators take advantage of Scala’s lenient method invocation syntax—Scala does not require a dot (.) between the object reference and method name.

These two features combined give the illusion of operator overloading. So, when you call ref1 + ref2, you’re actually writing ref1.+(ref2), and invoking the + method on ref1.

Let’s look at an example of providing the + operator on a Complex class that represents complex numbers. Complex numbers, as we know, have a real part and an imaginary part, and they’re useful in computing complex equations that involve the square root of negative ...