SE-0242 introduced major improvements to one of Swift’s most commonly used features: memberwise initializers for structs.
In earlier versions of Swift, a memberwise initializer was automatically created to accept parameters matching the properties of a struct, like this:
struct User {
var name: String
var loginCount: Int = 0
}
let piper = User(name: "Piper Chapman", loginCount: 0)
In Swift 5.1 this has been enhanced so that the memberwise initializer now uses default parameter values for any properties that have them. In the User
struct we’ve given loginCount
a default value of 0, which means we can either specify it or leave it to the memberwise initializer:
let gloria = User(name: "Gloria Mendoza", loginCount: 0)
let suzanne = User(name: "Suzanne Warren")
This lets us avoid repeating code, which is always welcome.
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