【Swift 60秒】50 - Returning values from a closure

0x00 Lesson

Closures can also return values, and they are written similarly to parameters: you write them inside your closure, directly before the in keyword.

To demonstrate this, we’re going to take our driving() closure and make it return its value rather than print it directly. Here’s the original:

let driving = { (place: String) in
	print("I'm going to \(place) in my car")
}
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We want a closure that returns a string rather than printing the message directly, so we need to use -> String before in, then use return just like a normal function:

let drivingWithReturn = { (place: String) -> String in
	return "I'm going to \(place) in my car")
}
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We can now run that closure and print its return value:

let message = drivingWithReturn("London")
print(message)
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