I'm continuing to work on the Head First Design Patterns book in an effort to become a more efficient and better Python programmer. Code review for the Strategy pattern in Chapter 1 is here with helpful explanations from the community.

I'm continuing to work on the Head First Design Patterns book in an effort to become a more efficient and better Python programmer. Code review for the Strategy pattern in Chapter 1 is here with helpful explanations from the community.

I've tried to implement the Observer design pattern from chapter 2 below in Python. In the book all the examples are in Java. I'm sure there are more pythonic things that I can do to this code. In the first example in this chapter we implement the Subject so that it pushes data out to the individual observers. In my code I wanted the Subject to notify the observers that new data was available, and have the observers pull only the data that each individual observer was interested in. I also tried to unit test instead of just printing output.

I've tried to implement the Observer design pattern from chapter 2 below in Python. In the book all the examples are in Java. I'm sure there are more idiomatic Python things that I can do to this code. In the first example in this chapter we implement the Subject so that it pushes data out to the individual observers. In my code I wanted the Subject to notify the observers that new data was available, and have the observers pull only the data that each individual observer was interested in. I also tried to unit test instead of just printing output.