Creating your own structs

Swift lets you design your own types in two ways, of which the most common are called structures, or just structs. Structs can be given their own variables and constants, and their own functions, then created and used however you want.

Let’s start with a simple example: we’re going to create a Sport struct that stores its name as a string. Variables inside structs are called properties, so this is a struct with one property:

struct Sport {
    var name: String
}

That defines the type, so now we can create and use an instance of it:

var tennis = Sport(name: "Tennis")
print(tennis.name)

We made both name and tennis variable, so we can change them just like regular variables:

tennis.name = "Lawn tennis"

Properties can have default values just like regular variables, and you can usually rely on Swift’s type inference.

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