func unsafeUnwrap<T>(_: T?) Returns: nonEmpty!. Requires: nonEmpty != nil. In particular, in -O builds, no test is performed to ensure that nonEmpty actually is non-nil. Warning: Trades safety for performance. Use unsafeUnwrap only when nonEmpty! has proven to be a performance problem and you are confident that, always, nonEmpty != nil. It is better than an unsafeBitCast because it's more restrictive, and because checking is still performed in debug builds. Deprecated: Will be removed in Swift 3. Use Optional.unsafelyUnwrapped property instead.. Declaration func unsafeUnwrap<T>(nonEmpty: T?) -> T