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iOS

Posted by jon kelson
jon kelson
5,149 Points

hi can someone help me with the answer to this maltiple choice question

hi can someone help me the answer to this question

var foo: String? = "bar" var baz = foo?.isEmpty

what is the inferred type of baz?

  1. Bool!

  2. the code will not compile

  3. Bool

  4. Bool?

1 Answer

Tassia Castro
.a{fill-rule:evenodd;}techdegree
Tassia Castro
iOS Development Techdegree Student 9,170 Points

Hey Jon,

The right answer is 4.Bool?

Why?

Because when you do this foo?.isEmpty you are using Optional Chaining. So it consequently returns an optional value that in this case was a Bool.

Check this link about optional chaining it may help you. example link