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.
SPONSORED Let’s face it, SwiftUI previews are limited, slow, and painful. Judo takes a different approach to building visually—think Interface Builder for SwiftUI. Build your interface in a completely visual canvas, then drag and drop into your Xcode project and wire up button clicks to custom code. Download the Mac App and start your free trial today!
Sponsor Hacking with Swift and reach the world's largest Swift community!
Link copied to your pasteboard.