For example, the types String and Int are both subtypes of Any.Īny is the equivalent of Java’s Object class. Starting from the TopĪll types of Kotlin object are organised into a hierarchy of subtype/supertype relationships.Īt the “top” of that hierarchy is the abstract class Any. Thanks to those rules, Kotlin can provide useful, user extensible language features – null safety, polymorphism, and unreachable code analysis – without resorting to special cases and ad-hoc checks in the compiler and IDE. Those rules combine together consistently and predictably.
Kotlin’s type hierarchy has very few rules to learn. That’s a shame, because I find it to be really neat 1. But I’ve not found an article that describes in one place how Kotlin’s type hierarchy fits together. Kotlin has plenty of good language documentation and tutorials. A Whirlwind Tour of the Kotlin Type Hierarchy
0 kommentar(er)
