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iOS Build a Weather App Dark Sky API Client Interacting With the API

Peter Correa
Peter Correa
17,155 Points
Posted by Peter Correa
Peter Correa
17,155 Points

What causes the lazy property 'baseURL' to return an optional URL?

Around 2:27 in the video.

1 Answer

Ian Billings
PLUS
Ian Billings
Courses Plus Student 7,494 Points
Ian Billings
Ian Billings
Courses Plus Student 7,494 Points

Hi Peter,

If you take a look at the Apple Documentation for URL object: https://developer.apple.com/documentation/foundation/url

The reason it returns an optional is because the initialiser for the URL object, that takes a String is a fail-able initialiser. This is because in reality any String can be based to the initialiser, and it may or may not be a valid URL. In the case that it is not valid, it will return nil. E.g. let url = URL(string: "hello world") would return nil, as "hello world" is not a valid URL, though it is a valid String.

Hope that makes sense.

Ian