Ooops - Constructor section, polymorphism section

[abrennec]

Hi,
I would like to suggest two improvements to the oop chapter: 1 concerns the subsection "Make even more Objects from your Class: properties and constructors"; 2 concerns the subsection "Quick intro to polymorphism (inheritance)".

1 - Following the section title, I would expect that the class constructor is going to be explained and used, i.e., Ball:Ball(). As far as I understand the code examples and section description, however, it does not actually describe what a class constructor is and how it is different from a normal function like, i.e., setup(). This should be improved, I suggest.
A quick resolution would be to simply change the section title to "Make even more Objects from your Class" (and add a reference to more details on constructors). My question regarding this issue is, why isn't the constructor being used?

2 - Polymorphism is not sufficiently described in the example. A fix would be changing the title to "Quick intro to inheritance".