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Updated for Xcode 16.4
As great as SwiftUI is, it’s fair to say that its error messages can sometimes be a little unhelpful. Often you’ll get an error on line 5 when really the error is on line 10, and its common for the messages you do get to be hard to understand.
Although it’s not possible for me to diagnose every error you might hit, in this appendix we walk through all the most common error messages people seem to hit, then provide example code to solve it so you can move on.
If none of these solutions have helped you, the best thing to do is a binary chop for your code: remove a few things and see if that works, then remove a few more things and a few more, until eventually your code compiles. You can then re-add the part that causes the problem, and try to fix it.
Please keep in mind that SwiftUI leverages all of Swift’s most advanced features – the error messages are going to improve, but it might take a little time.
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