How do you use the Optional variable in a ternary conditional operator?

Question

I want to use an Optional variable with the ternary conditional operator but it is throwing error this error: optional cannot be used as boolean. What am I doing wrong?

var str1: String? var myBool:Bool myBool = str1 ? true : false 

Answer 1

You can not assign string value to bool but You can check it str1 is nil or not like this way :

myBool = str1 != nil ? true : false print(myBool) 

It will print false because str1 is empty.

Answer 2

Nil Coalescing Operator can be used as well. The code below uses the ternary conditional operator and forced unwrapping (a!) to access the value wrapped inside a when a is not nil, and to return b otherwise

Normal Ternary Operator :

output = a != nil ? a! : b Apple Developer Link : Please refer to Demo Link

In Swift 1.2 & 2, above line of code is replaced by a shorter format:

output = a ?? b 

Demo Link : The nil coalescing operator (a ?? b) unwraps an optional a if it contains a value, or returns a default value b if a is nil.