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iOS Swift Functions and Optionals Optionals Optional Chaining

Posted by Pierre-Emmanuel Turcotte
Pierre-Emmanuel Turcotte
13,670 Points

Why no if Let unwrapper to use sendNotice() after chaining ToInt to findApt("101")?

Since the chained function ToInt() also returns an optional, why do we get rid of the if let unwrapper?

1 Answer

Ezekiel Elin
Ezekiel Elin
3,839 Points

sendNotice() doesn't return any values. Therefor it doesn't require unwrapping while calling it.

when you use toInt, by using an if let statement, you are unwrapping the integer and making it non optional. Now that you have unwrapped it, the if statement calls sendNotice(). Because sendNotice() is inside the if statement, it only happens if the optional is not nil.

If it was nil, the if statement didn't run, it wouldn't call sendNotice()