I will try to make the explanations clearer, I'm still trying to improve my writing and this is very much appreciated, oh, and the code is Ruby.
I forgot to add the source code for the article, I just pushed it to a git repo and added a link to it at the article's footer.
Thanks again!
In school, I believe I heard this summarized as something along the lines of: "a derived class should require no more and deliver no less than its base class". I have always liked that succinct phrasing of the principle.
Uh, very nice, I need to write that down, it's by far the most concise version of the principle I've heard!
Thank you