Question

Is it possible to overload the index operator in Scala?
If yes, what would the scala version of this c++ example look like?

class Foo {
  int data[7];
  ...
public:
  int& operator[](size_t i) { return data[i]; }
  int  operator[](size_t i) const { return data[i]; }
  ...
};

Answer 1

The index operator in scala is (), and you can define a method which looks like it. You need to define an apply method.

scala> class Foo(v: String) { def apply(i: Int) = v(i) }
defined class Foo

scala> val f = new Foo("foobar")
f: Foo = Foo@c3dd7e

scala> f(3)
res3: Char = b