U3L2 (Optional and Failable Initializers)

Front

What is a failable initializer?

Back

An initializer that may fail and return nil.

Tags

U3L2

Front

What might happen when you use the force-unwrap operator (!)?

Back

The app may crash if the optional value is nil

Tags

U3L2

Front

What is an implicitly unwrapped optional?

Back

An optional value that can be used without unwrapping.

Tags

U3L2

Front

What is a nested optional?

Back

An optional value that contains another optional.

Tags

U3L2

Front

What does nil indicate?

Back

A value that is missing.

Tags

U3L2

Front

What is an optional?

Back

An optional represents two possibilities: Either there is a value and you can use it, or there isn't a value at all.

Tags

U3L2

Front

What is optional binding?

Back

The process of assigning an optional value to a constant and this process returns "true" is there is a value and "false" if no value is present.

Tags

U3L2

Front

What does optional chaining allow you to do?

Back

Work with nested optionals

Tags

U3L2

Front

[U3L2] What happens if any value along the optional chaining is nil?

Back

The action will fail

Tags

U3L2

Front

What is a force-unwrap?

Back

This accesses the underlying value of an optional. This may crash the app if the optional value is nil

Tags

U3L2