Programming with Values

Warmup

• What does ‘single responsibility’ mean in a programming context?
• How does programming with an eye towards the single responsibility principle help us as programmers?
• In past projects, what have you decided to test? What have you decided not to test?
• Why?

Coding for Yourself

• Create classes that you want to use.
• Create classes that you want to test.
• Create classes that allow you to reuse them.
• Create classes that allow you to use the tools you’re most comfortable with.

Creating Interfaces/Adaptors

• An interface is a way to interact with the outside world.
• If your program were a video game, the interface would be the controller.
• We need interfaces to interact with people.
• We want to design programs for people.
• We also want to make our program easy to work with.
• Creating isolated interfaces allow us to deal with the messiness of people and data without letting it infect our code.

Values vs. Locations

• Using locations in your code is a sign that you could create an interface.
• Instead, use the things you like:
  • hashes
  • arrays
  • strings

Exercise: Pizza Parlor

Link here

Share

• What did you test?
• What didn’t you test?
• Can you test more if you refactored your code?

Review Potential Refactors

• Can we isolate the file I/O?
• Can we extract it to a class?