“Functions are a first-class type” in swift?

Question

the little knowledge , I have about first class function is that it supports passing functions as arguments and we can also return them as the values in another function ... I a

Answer 1

Any programming language is said to have first-class-functions, when functions are treated like normal variables. That means a function can be passed as parameter to any other function, can be returned by any function and also can be assigned to any variable.

i.e., (Referring apple's examples)

Passing function as parameter

func hasAnyMatches(list: [Int], condition: (Int) -> Bool) -> Bool {
    for item in list {
        if condition(item) {
            return true
        }
    }
    return false
}

Returning function

func makeIncrementer() -> ((Int) -> Int) {
    func addOne(number: Int) -> Int {
        return 1 + number
    }
    return addOne
}