C++ is the prime example of what the alternative looks like.
My girlfriend has decided to learn programming. She started with Swift because she wanted to write iOS apps. The course she's using targets Swift 2 but her install is Swift 3, or something like that (I haven't looked into it much).
XCode constantly flags stuff like x++ being replaced with x += 1. Really? Surely that's the kind of decision you make before version one of a language, not years after release. Why this pointless churn?
If these sorts of totally-indecisive deprecations were rare then you could overlook them, as otherwise Swift is a rather nice language. But they're everywhere. Even in trivial examples intended for beginners line after line of code gets the yellow deprecation warnings. "What does deprecated mean" was literally one of the first questions my girl asked me as she started out learning programming, which is ludicrous. You shouldn't be encountering deprecation warnings over and over when targeting a brand new platform using a teaching course barely a year old.
I think that this kind of break is not that bad, swift is a young language, and there are some things that only after so much testing you realize it could be better.
Swift is 2.5y old, it has just one year being open source, so I don't think these breaking changes as a big deal. It is not in a situation like Python 3. Even the compiler helps you fix it and XCode is very helpful when translating Swift 2 to Swift 3, so it is not that bad.
Of course, age only tells you so much about the amount of work put into the project, and Rust in particular took a huge amount of conceptual work to get its current model of ownership.
Changes to Swift are hardly indecisive or pointless. A very clear rationale for removing the ++ operator was laid out here: https://github.com/apple/swift-evolution/blob/master/proposa....
While these changes may be painful now (though the removal of the ++ operator seems minor to me), they should result in a stronger and simpler language in the long run.
Removing x++ is indeed minor, which is why it's so curious. Sure, there are arguments for removing it. But there are also arguments for minimising language churn and just living with these things.
Definitely going against the general language trend, there.
And the justifications to remove ++ are downright bizarre in my opinion.
Btw, Xcode still doesn't support refactoring Swift code
And in spite of all problems with Java and its standard library, there's something very liberating about having code written in 1997 that still compiles and works in 2017.
And the beauty of Java is that it became a platform, so if you hate the language, you can pick another that's closer to what you think programming should be, like Scala, Clojure, JRuby, Groovy, Kotlin, etc. and still benefit from that piece of code written in 1997, all made possible due to Sun's fanatical devotion to backwards compatibility.
Where Swift excels is that it has the performance of C for the most part, and it will continue to improve. Another strength is ARC over Java style GC. As the slides point out, to get the same performance with GC, you need 4x the memory. With only 2x the memory, you get 70% lower performance with Java. Most important, though, is determinism. GC is simply not suitable for real time, hard or soft.
I'm very excited about Swift, and the current version of Xcode is working pretty well for me. I love the aggressive goal of replacing the C family of languages down the road...
I'd take that claim with a pretty big grain of salt. The paper they referenced used an experimental GC without use in production. Who knows how well or bad the default collector in the JVM would perform.
Also, it is not exactly recent. Hardware changes could have shifted the result in any direction.
Regardless, determinism is the really big win. :-)
That said, if you're looking for a language that has kept backwards compatibility, that's Clojure. Rich Hickey has a recent keynote that I found very interesting: https://www.youtube.com/watch?v=oyLBGkS5ICk
I don't know how to feel about it. On one hand this means Clojure will probably never fix some obvious mistakes in its standard library, without changing its name (like what they did with ClojureScript). On the other hand, as I said, it is liberating to have code written in Clojure 1.0 still working in 1.8.
Yes, like the "courage" it takes to remove the 3.5mm headphone jack.