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David Keck
5,723 PointsQuestion on assignment syntax used
Why is the ? present in the code below?
person?.apartment = apartment
I know I should know this, but I can't recall.
1 Answer
David Keck
5,723 PointsFrom The Swift Programming Language:
“When working with optional values, you can write ? before operations like methods, properties, and subscripting. If the value before the ? is nil, everything after the ? is ignored and the value of the whole expression is nil. Otherwise, the optional value is unwrapped, and everything after the ? acts on the unwrapped value. In both cases, the value of the whole expression is an optional value.”
Excerpt From: Apple Inc. “The Swift Programming Language (Swift 2.1 Prerelease).” Apple Inc., 2016-02-17T08:00:00Z. iBooks. This material may be protected by copyright.
Check out this book on the iBooks Store: https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewBook?id=1002622538