Well, Apple’s done it again, and made func parameters even simpler in Swift 3.0!

It’s all very straight forward now, class methods, static methods, global functions, init methods – they all work the same now, hooray!

1. Explicit parameter names

ALL parameter names by default are explicit:

class Person {
    init(firstName:String,surname:String) {
        (firstName,surname)
    }
}
var person = Person(firstName: "Tim", surname: "Cook")

2. External parameter name

The same parameter can have a different name externally and internally. This could be useful if different names make more sense depending on the perspective, or even for different human languages – perhaps the developer speaks a different language to the user of the class. The external parameter name comes first.

class Person {
    init(firstName 名字:String,surname 姓:String) {
        (名字,姓)
    }
}
var person = Person(firstName: "Tim", surname: "Cook")

3. implicit external parameter name

If for some reason you want your external parameter names to be implicit, you can use this external parameter name construct, and represent them with underscores:

class Person {
    init(_ firstName:String,_ surname:String) {
        (firstName,surname)
    }
}
var person = Person("Tim", "Cook")

For more on functions in Swift, check out my video:

About craiggrummitt

iOS development with Swift - book: https://manning.com/books/ios-development-with-swift video course: https://www.manning.com/livevideo/ios-development-with-swift-lv