MCE 2017: Svetlana Isakova, Coroutines in Kotlin

Svetlana Isakova explains the concept of coroutines in Kotlin, comparing them to lightweight threads and async-await patterns.

The async/await feature allows you to write the asynchronous code in a straightforward way, without a long list of callbacks. Used in C# for quite a while already, it has proved to be extremely useful. In fact, async/await is an implementation of a more general concept of coroutines, which first appeared more than 50 years ago. Coroutines are essentially light-weight threads that can be suspended and resumed later. Kotlin brings to the table the native support for coroutines, allowing to implement async/await, yield and similar programming patterns as different libraries, not built-in language constructs. The separate library for RxJava, for instance, can declare 'asyncRx' returning Observable and the 'await' function as an extension on Observable. In this talk we'll start with the essence of async/await and then proceed to the general concept of coroutines with some details of how it's implemented in Kotlin.