How to use map() with an optional value
The map() method of optionals allows you to transform the optional if it has a value, or do nothing if it is empty. This makes for shorter and more expressive code than doing a regular unwrap, and doesn’t require you to change your data type.
For example, if you had an optional string like this one:
let name: String? = "twostraws"You could use the map() method to transform it safely, without having to check and unwrap it – if it were nil, the map() call would do nothing.
For example:
let twitterName = name.map { "@\($0)" }
print(twitterName)That will print @twostraws.
Available from iOS – learn more in my book Pro Swift
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