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iOS

Posted by Jun Da Ma
Jun Da Ma
2,266 Points

what happens if i don't use ELSE to unwrap an optional and the value returned is nil?

If let statement allows us to unwrap optionals. What happens if we don not use the else statement in conjunction and the value returned was actually nil?

I am thinking that the code will just not execute. However the app will not crash as is the case if optional was not used at all.

1 Answer

Martin Wildfeuer
Martin Wildfeuer
Courses Plus Student 11,071 Points 
// test is optional and nil
var test: String?

if let unwrappedTest = test {
   // You can only use unwrappedTest in this context
   // and only if test != nil
   // All code that does require a non-nil test belongs here
}

// test is still optional here, nil in this case 
// unwrapped test is not defined here

You don't necessarily need else if you simply don't want to execute any code if test is nil.

As a sidenote, Swift 2 introduces the guard statement, which is most probably what you are up to.

Jun Da Ma
Jun Da Ma
2,266 Points

hey thanks so much for the answer and for elaborating on it. That was exactly what i wanted to know.