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iOS Build an Interactive Story App with Swift Refactoring Our Code Immediately Executing Anonymous Functions

Haifa Bassam
Haifa Bassam
10,333 Points

Error: Expression is not assignable: function call returns immutable value

when I write this code:

let storyLabel = UILabel() = {
    let label = UILabel()
    label.translatesAutoresizingMaskIntoConstraints = false
    label.numberOfLines = 0
    return label

I get an error:

Expression is not assignable: function call returns immutable value

Any clues why?

2 Answers

Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

Your issue is on the first line:

let storyLabel = UILabel() = {

It looks like you are trying to set the type of the storyLabel constant to UILabel. Instead you are assigning the constant to a new UILabel instance and then trying to assign the result of the UILabel initializer to the closure result.

To set the type pf the constant, you should use this:

let storyLabel: UILabel = {