Understanding null safety in Dart

I believe Dart is a more exciting language than Go. It&#x27;s the most well designed scripting language out there, that can also be AOT compiled into native binaries. It&#x27;s a better JS and a better Java at the same time. It would be also a killer language for backends and simple websites. Just imagine a better node.js built around Dart&#x27;s excellent tooling.<p>What made Go more successful than Dart was a mix of decisions, luck, and momentum. On an alternate reality, Dart would swap places with Go. Dartium VM would have replaced Javascript on the Web and everyone would have been happy. Go would be seen as an obscure language with missing features that doesn&#x27;t really do anything better than java&#x2F;C#&#x2F;C++

Does Dart2 offer any compelling features as a language that aren’t also present in Kotlin, Typescript, Swift, or Haxe? I know many users are interested in Flutter - but I’m curious more about the language itself. Whenever I see Flutter examples I’m disappointed I can’t use it with Kotlin (which already has many specialized backends) or some other language with more widespread support outside the Google ecosystem.

Null safety is absolutely essential for me. It&#x27;s 2020, why are we still having NullPointerExceptions? However I&#x27;m curious about the next frontier of safety. We&#x27;ve slowly added a lot of nice features around safe use of values and safe memory. I wonder what&#x27;s next.<p>Personally I&#x27;ve been thinking about safe use of arrays. Arrays are such an important data structure and yet they&#x27;re horribly unsafe. Every time I do index math I get that same nervousness that I used to get accessing fields in nullable data structures. I&#x27;d love for a way to verify array indices that doesn&#x27;t involve too much dependent typing.

Not a Dart programmer, but looking at it for flutter. I see from Jetbrains Developer Survey[1] that Dart has grown to 9% from 6% last year[2] which I think is because of flutter, which has grown its share to 39% in cross-platform development.<p>But doesn&#x27;t it seem reasonable to use TypeScript for flutter now? If you are not a Googler, Where do you use Dart (outside flutter) in production for a purpose where it is better than TypeScript?<p>[1]<a href="https:&#x2F;&#x2F;www.jetbrains.com&#x2F;lp&#x2F;devecosystem-2020&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.jetbrains.com&#x2F;lp&#x2F;devecosystem-2020&#x2F;</a><p>[2]<a href="https:&#x2F;&#x2F;www.jetbrains.com&#x2F;lp&#x2F;devecosystem-2019&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.jetbrains.com&#x2F;lp&#x2F;devecosystem-2019&#x2F;</a>

I&#x27;m very happy about this - lack of null safety and implicit downcasts are two of the biggest problems with Dart&#x2F;Flutter, which I otherwise really enjoy working in. I&#x27;ve gotten in the habit of adding &quot;assert(x != null)&quot; in all of my methods.

Dart is one of my favourite languages right now. I know it gets a lot of criticism for not reinventing the wheel and being heavily OOP based, but it&#x27;s simple enough, standard library works well, IDEs work great. Also it actually has some unique features which I now miss from other OOP languages, such as named constructors - new Angle.fromRadians(...), new Angle.fromDegrees(...) - feels much cleaner and more self-documenting than the static factory method other languages have you use.<p>Optional typing I never really cared about, because even in languages with var I find myself writing the types whenever possible.

I used flow typing in MyPy and it&#x27;s awesome. TypeScript has the same thing (although I would be curious if their rules are significantly different).<p>I think you can&#x27;t practically have null safety without flow typing, at least in an imperative language, otherwise you end up with casts everywhere. MyPy has null safety, though it takes some effort to turn it on for most codebases.

I&#x27;m really hoping this will make AngularDart a lot nicer to write. Inputs might have a null value and it&#x27;s very easy to forget to account for it, will be great to catch that at compile time.

Looks to be very close to the solution Zig also went for. I like the solution and it seems to fit both languages very well. I should look a bit further into Dart some time I think.