Warm greetings! This lesson introduces data streams, which are essentially continuous datasets. Think of a weather station or gaming application gathering data per second — both generate data streams! We will master handling these data streams using Kotlin, learning to access elements, slice segments, and convert these streams into strings for easier handling.

In Kotlin, data streams can be represented using arrays or lists. Kotlin's syntax and powerful type inference mean that we don't need explicit type annotations as in some other languages.

Consider a straightforward Kotlin class named DataStream. This class encapsulates operations related to data streams in our program:

To use it, we create a sample data stream as an instance of our DataStream class, where each element is a DataElement object with two properties, id and value:

To examine individual elements of a data stream, we use indexing. The method we introduce below fetches the -th element from the data stream and returns a nullable type to handle cases where the index might be out of bounds: