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iOS Swift Functions and Optionals Functions Function Return Types

James Robertson
James Robertson
1,934 Points
Posted by James Robertson
James Robertson
1,934 Points

Return Types code challenge.

I have been stuck on this challenge for a while and cant work out why the output is not Hello Tom, even though I have specified Println("hello (greeting)").

The aim of the challenge was to create a return type to display Hello Tom. I have run out of ideas :(

returns.swift 
func greeting(person: String) -> String {
    return person
}

println("Hello \(greeting)")
James Robertson
James Robertson
1,934 Points
James Robertson
James Robertson
1,934 Points

Don't worry, solved it! Didn't need the Println statement after all... this code worked: 

func greeting(person: String) -> String {

    let greeting = "Hello" + person"
    return greeting

}

3 Answers

rtprjct
rtprjct
30,548 Points
rtprjct
rtprjct
30,548 Points

Your function is correct, when you call it, you need to give it the string "Tom" 

println("Hello " + greeting("Tom"));
Mike Atkinson
Mike Atkinson
6,882 Points
Mike Atkinson
Mike Atkinson
6,882 Points

Yes as artie91 said, you need to pass an argument to the function.

When declaring, the part in the round brackets is the parameter. To call a func, you need to supply it with the required argument(s) to match the parameter(s).

For example here "SomeString" is the argument to match the parameter (person: String).

//declaring with one parameter
func greeting(person: String) {}
//calling with one argument
greeting("SomeString")

a func can have 0,1, or more parameters.

eg.

//Declaring
func newFunc() {
    println("Funky")
}

//calling
newFunc()
//prints "Funky"

Highly recommend about functions here, at the apple developer library.

Whitman Huntley
Whitman Huntley
6,811 Points
Whitman Huntley
Whitman Huntley
6,811 Points

This did it for me.

func greeting(person: String) -> String {

let greeting = "Hello \(person)"
return greeting

}

println(greeting("Tom"))