One of my absolute favorite collection refactorings is to combine the
contains methods with higher order functions to turn repetitive loop-heavy code into short, expressive solutions that read like human speech.
In this quick screencast, I go over an example of how I used this approach combined with the Null Object pattern to clean up some duplication in the Nitpick CI codebase.
If you enjoyed this screencast, check out my new book + video course, "Refactoring to Collections".
It covers fundamental topics like imperative vs. declarative programming, understanding higher order functions, and includes 4 hours of screencasts going over refactorings like the one in this post.
Check out the website to learn more, or subscribe below for a free chapter sample.