Reviewing Kotlin data structures

There are three important groups of data structures we should become familiar with in Kotlin: lists, sets, and maps. We’ll provide a brief overview of each here, and then delve into topics related to data structures, including mutability and tuples, in more detail in Chapter 5, Introducing Functional Programming.

Lists

A list in Kotlin represents an ordered collection of elements of the same type. To declare a list, we utilize the listOf() function instead of calling the constructor of a specific list implementation. This function provides a convenient way to create a list and initialize it with elements:

val hobbits = listOf("Frodo", "Sam", "Pippin", "Merry")

It is important to note that we didn’t explicitly specify the type of the list. This is because type inference can be employed when constructing collections in Kotlin, similar to initializing variables.

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