Swift Structs

A struct is similar to a C++ Struct. You are essentially just creating your own data type

This is what it would look like to declare a struct

struct Person{
	let name: String
	let age: Int
}

To instantiate a struct variable it would look like this

let foo = Person(name: "Foo", age: 20)

You can access the properties of a struct using Dot Notation

foo.name
foo.age

For structs constructors are implicitly created so you do not need to declare one although you can. For this structs are preferable over classes in Swift.

This is how you would create a custom constructor for your struct

struct CommodoreComputer{
	let name: String
	let manufacturer: String
 
	init(name: String){
		self.name = name
		self.manufacturer = "Commodore"
	}
}

A constructor will have the keyword “init” which would be the only keyword for this special “function”

Structs also have Computed Properties

So far all the structs above have been immutable

How would a mutable struct look like?

struct Car{
	let currentSpeed: Int
	
	mutating func drive(speed: Int){
		"Driving..."
		currentSpeed = speed
	}
}

You need to use the mutating keyword before the func keyword. This tells the swift compiler that this function is going to be changing the values in the struct. While this can be done this is bad practice and shouldn’t really be done in a struct.

Swift structs do not have SubClassing