Swift 3: What You Need to Know About Implicitly Unwrapped Optionals

I keep having a hard time remembering how Implicitly Unwrapped Optionals (IUOs) work in Swift 3, so I went back and watched that part of the What’s New in Swift WWDC16 talk again. This time, I want to write it down as a reference to myself and for anyone else who needs it.

The main thing to remember is that IUOs will only be force unwrapped if they need to be type checked locally. Otherwise, they will be kept as optionals. This should reduce bugs when IOUs are truly needed to be used!

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  • >The main thing to remember is that IOUs will only be force unwrapped if they need to be type checked locally. Otherwise, they will be kept as optionals. This should reduce bugs when IOUs are truly needed to be used!

    You mean IUOs right?

  • Dinesh Kumar

    Crisp and to the point. I like your posts.

  • Lev Sokolov

    Thank you