You could potentially do the same thing with a class but it'd be really verbose:

Class Age {

  private int value = null;

  public boolean SetValue(int value) {
    if (value >= 0 && value <= 150) {
      this.value = value;
      return true;
    }
    return false;
  }

  public int getValue() {
    return this.value;
  }

}

That's approximately what the equivalent would look like in any language that supports classes (any errors are because it was typed on my phone). Being able to do that in 1 line would be much more convenient. That's why most programmers working in those languages just define age as an int and move on.