Optionals: A Gift to Unwrap
Optionals are a unique feature of Swift, and they are used absolutely everywhere. Optionals take a little getting used to but in the end they are a clever feature that helps you achieve clean-looking code with fewer lines while also being stricter.
In many languages, you need to check objects to see whether they are nil
or null
. Usually, you write some pseudo-code that looks like the following. In this example we check for not null in Javascript:
if(something != null) {...
Not having to write that ugly code all over the place saves you time. In Swift, an optional value contains either a value or nil
to indicate that the value is missing. To mark something as optional, you just include a ?
next to the type of the object. ...
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