Swift 2.2 formally deprecates the ++ and -- operators, which means they still work but you'll get a warning when you use them. Deprecation is usually a first step towards removing something entirely, and in this case both of these operators will be removed in Swift 3.0.
In their place, you need to use += 1 and -= 1 instead. These operators have been there all along, and are not going away.
You might wonder why two long-standing operators are being removed, particularly when they exist in C, C#, Java, and – critically to its "joke" – C++. There are several answers, not least:
- Writing
++rather than+= 1is hardly a dramatic time saving - Although it's easy once you know it,
++doesn't have an obvious meaning to people learning Swift, whereas+=at least reads as "add and assign." - C-style loops – one of the most common situations where
++and--were used – have also been deprecated, which brings me on to my next point…
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Other changes in Swift 2.2…
- Traditional C-style for loops are deprecated
- Comparing tuples
- Tuple splat syntax is deprecated
- More keywords can be used as argument labels
- Variable parameters have been deprecated
- Renamed debug identifiers: line, function, file
- Stringified selectors are deprecated
- Compile-time Swift version checking
Download all Swift 2.2 changes as a playground Link to Swift 2.2 changes
