Please note, this blog entry is from a previous course. You might want to check out the current one.
Lecture #3 continues the calculator demonstration, adding the model to the MVC pattern. In addition he shows how to use
- enums,
 - simple initializers,
 - returning optionals,
 - dictionaries,
 - and tuples.
 
The lecture is available via iTunes named “3. Applying MVC”. The code for the demo is available on GitHub.