Dictionary and Set Improvements in Swift 4.0

Swift 4 added a lot of really awesome Dictionary and Set APIs. Operations like grouping, filtering, and transforming values are easier than ever, and can be performed in a single step. In this post on the official Swift blog, Nate Cook explores these new APIs. It’s also worth noting that most of the changes mentioned are available in Swift 3.2, so even if you have not yet moved to Swift 4, there is something here for you.