Show HN: Programming Google Flutter with Clojure(github.com) This proof-of-concept project combines:
- Flutter, from Google;
- ClojureDart, port of Clojure to Dart from Tensegritics; and
- Matrix, a reactive framework from moi. So, yes, we can now program Flutter with a Lisp. Yay. Project includes dozens of working examples and a full implementation of the TodoMVC classic to help tire-kickers play around. Support installing freely available on the #matrix channel on the Clojurians Slack. |
Lots of interesting stuff happening in the Clojure space lately.
https://github.com/squint-cljs
It's a strange thought, but I wonder if Clojure (or rather, the clojure community) would somehow "migrate" from the jvm at this rate.
Clojure has always been about being hosted on different platforms. The best Clojure development experience is probably full-stack Clojure, i.e. JVM Clojure on the backend and ClojureScript on the web—and perhaps ClojureDart for apps. People are implementing Clojure on different hosts because they love the language and want to use it in other contexts, not because they don't like the JVM.
I actually wrote about this phenomenon a few years ago and it reached the top of HN: https://news.ycombinator.com/item?id=22458827
I should probably revisit the topic again, since much has changed in the meantime.
It's because Clojure isn't intended to "hide away" the platform underneath and you interact with the platform quite a bit. Since I prefer Rust ergonomics over Java/JVM ergonomics, it'd be awesome to have Rust as a Clojure platform.
One day it will happen - if not by me, then by someone else, I'm sure!
Rust has a relatively thin runtime, but heavy static compilation work (types and lifetime and borrowing, etc...) , so it kinda seems like a completely different set of tradeoffs than what clojure favors (dynamicity, late bindings, runtime checks, managed memory, etc..)
Or did you mean "a clojure-like syntax for something that produces rust code to be eventually compiled natively ?"
Carp is a statically-typed, GC-less Lisp that implements Rust’s borrow-checking. It is implemented in Haskell and compiles to C. It shares some syntax with Clojure, but I wish it was more Clojurey.
As for migration, Mr. Hickey made a small language, and that made CLJS and CLJD possible. Nice! Now they just have to bring CLJD under the CLJC umbrella...but I suspect that would be a stretch.
I really want to learn clojure and use flutter for a personal project... are there are any reasons not go down this path? (E.g. the "official" implementation of flutter is more secure?, etc.)
Thank you for the cool project
Unless I misunderstand your question, this has already been possible for some time: ClojureScript + React/React Native.
There are some impressive videos illustrating this. The devil is in the tooling and setup, but once that is in place the pace and ease of development looks great.
It's really amazing to make a code change in my text editor and see the UI on my mobile app update instantly.
ClojureScript & the user base has since steadily grown and improved and people have been shipping serious production applications with it for a long time now.
Matrix has many widgets yet unwrapped, but I will document the wrapping process and support any user by doing the wrapping myself. I also have in mind developing a Dart tool to generate wrappers automagically.
tl;dr: ClojureDart is in great shape, Flutter/MX is solid but needs more widgets wrappe.
TL;RD; Functional Python on top of Flutter
From https://github.com/flet-dev/flet:
" Deliver to any device Deploy Flet app as a web app and view it in a browser. Package it as a standalone desktop app for Windows, macOS and Linux. Install it on mobile as PWA or view via Flet app for iOS and Android."
From https://coconut.readthedocs.io/en/latest/HELP.html:
"Specifically, Coconut adds to Python built-in, syntactical support for:
pattern-matching
algebraic data types
destructuring assignment
partial application
lazy lists
function composition
prettier lambdas
infix notation
pipeline-style programming
operator functions
tail call optimization
where statements"
Is there a state management solution in there? I looked at the Todo app and it looked like manual change propagation.
I was very keen on Flutter a few years ago until a version bump broke my one application and I never spent the time to fix it.
Clojure is far from my favorite Lisp, but I like it well enough. What will sell your project to me is how nice the dev process is. I love Common Lisp and Scheme dev process, but I struggle to get the same level of happiness with Clojure.
Looks like a nice project!
I hang mostly on the Clojurians Slack if you get stuck, #clojuredart or #matrix channels.
(Please say yes, please say yes, please...)
That was... six months ago. :) So... I guess I'll keep waiting.
Instead I get by with sub-second recompiles/reloads and print statements. It works great, tbh.
That said, Tensegritics is working on it.
Please let me know what else you might like to see.
The app rebuilds/reloads on save. Tensegritics is looking at better hot reloading; I am happy with automatic full restarts.
Flutter offers a couple of endpoints to visit for debuggers, but I just live off print debugging in the build console.
Video ASAP.
OTOH, so far I am OK with the idea of forever adding nested widgets just to add some styling, and making children implicit makes the code look less "busy", but look for me to sneak in soon a DIV macro supporting the classic HTML attributes. That will be fun!
The type system was verbose yet relatively weak in comparison to something like Typescript, it'd already been rewritten once (which isn't a bad thing), and it was almost unusable outside the platform (I remember trying to write tests for something using sqlite.dart and then realizing that you just... couldn't).
Flutter is an amazing technical achievement, and to some extent so is Dart (there's a great talk from strangeloop about it) but I just... want to be able to use anything but Dart in there. Being able to use Typescript with Flutter would be heaven (JS compatibility was something in early versions of Dart that was removed).
If you like Java 8 and earlier you'll probably feel at home with Dart.
Obviously I'm biased, but I find Dart to be one of the most unpleasant languages I've had the misfortune of being exposed to; this despite Flutter and its instantaneous hot code reloading being quite amazing -- a bizarre mix of promise and despair.
[1] https://github.com/dart-lang/language/blob/master/resources/...
I see a lot of solutions in the Flutter ecosystem and none getting raves, so I decided to throw my "reactive first" Matrix[2] hat into the ring. Feedback welcome.
[0] https://github.com/mobxjs/mobx [1] https://github.com/ThoughtWorksInc/Binding.scala [2] https://github.com/kennytilton/mxtodomvc#readme
Happy opportunity for ClojureDart!
btw, in case anyone is wondering, I am not a part of Team CLJD at all. My hack is my own separate effort.
However, the idea that you need a “Center” widget just to position an item to the center of its parent…it just feels like GUI development took a major step backwards. I really can’t grasp why that decision was made. I’m open to having my mind changed but so far I’m like, thanks I hate it.
Specifically, instead of doing random mish-mash of layout (like in every other UI toolkit I know, including HTML), Flutter has a simple layout protocol that defines how a parent lays out it's children.
It's a simple, local protocol. ("local" means that the effect of layout is local to widget doing the layout, unlike in HTML where some layout properties effect more than just immediate children).
`Center` is a simple widget that lays out its child in the center of itself.
Why is it good and coherent design?
What if you need to position child 2/3rds on the X axis of the parent?
In Flutter you write (trivial) `Position23rdX` widget and you're done. An easy way to implement custom layout logic that plugs into a coherently designed layout protocol.
In HTML you can't. You can use layout properties that HTML gives or you're out of luck.
I've also worked (or dabbled) with win32 (no layout at all), WinForms, WPF, Cocoa, Gtk - none of them have anything like that.
As for what I call the "Lego model" of UI construction, while definitely off-putting, I think the "why" is prolly "simplicity thru decomposition". So we do a bit more typing but have a dead simple approach to building our UIs.
The nice thing about any Lisp with its macro capabilities is that we can wrap sth like Flutter to produce a library that remains Flutter, but hides the noise.
ClojureDart offers a so-called "widget" macro, and my Matrix library goes a different way, making every constructor such as "scaffold" into a friendlier macro.
I know, I have been beating on CLJD like I was its Daddy wrapping it in a reactive framework, despite their warning that there would be surprises. I had one problem that turned out to be a simple bug in CLJD.
I also follow their channel on the #clojurians Slack and see they are doing a profoundly deep job on the compiler. This means a robust product, not one that has developers forever looking over their shoulders at the language they are using.
Six months for that is nothing. Now send them eight dollars. jk. :)
The one caveat I offered was "...but a REPL will be a selling point!" ROTFL
Seriously, when I want a REPL I hack the test code into "main" and comment out the UI launch. Then I edit and save and the output goes to my terminal nearby thanks to auto build/restart.
cgrand's comment says: Not yet, but probably soon! Here's a link to donate
My comment says: Before you donate, here's some context for what "soon" likely means
Your comment says........?
I switched from a purely TS/JS stack (React-Native-Web to cover iOS/Android/Web, Typescript on the backend, with some stuff to share types), and just got way too tired of all the tooling, the configuration, etc.
While I use Golang on the backend (compiled to WASM for serverless) I wouldn't be against using Dart on the backend if it had a WASM compiler...
....and upon doing some research to put a link in here, apparently you can as of seven days ago? https://github.com/dart-lang/sdk/blob/main/pkg/dart2wasm/dar...
Dart was being pushed as JavaScript replacement, back when everyone had one.
However Chrome team failed to push ChromiumVM and eventually the project was ramped down, by then AdWords had made a massive investment moving from GWT into AngularDart, so they rescued the project.
Eventually Flutter, initally prototyped in JavaScript, moved into Dart, and they also decided to change the language semantics from dynamic language with gradual typing (Dart 1.x), to static typing with type inference (Dart 2.0).
Somewhere alongside this timeline, many well known names from language design like Gilad Bracha and Kasper Lund, well known for favouring dynamic languages, left the project.
Kasper Lund's latest project, is not surprising also a dynamic language, https://toit.io/
Another thing is Dart is JITed, AOT compiled as well as compiling to JS and WASM. Very few languages can do all 4. JVM ones can't, so no Kotlin (we'll see how well Kotlin Native works), and V8 isn't AOT so no JS or TS either. Only alternative I can think of is Lua.
> Very few languages can do all 4. JVM ones can't
Java can (JIT is trivial, for AOT there is among others Graal, for JS and WASM there is TeaVM (which works on class files, so now that I think about it, pretty much every JVM language can do all platforms), but also the very great Closure compiler (j2cl) which has no relation to cloJure, made and used heavily by google)
With your Java example, that's exactly what I mean, you don't need 4 different tools in Dart to achieve the 4 types of compilation, they're all included in the standard Dart compiler/SDK. Sure, if we go by your definition, probably any language has some level of support for each via various random compilers but I'm talking about something first-class, built-in.
And my specific contrib, Matrix, handles state management and the whole reactive thing pretty well, one area where I see a bit of thrashing in the Flutter community. Check out the examples and esp. the TodoMVC demo, they cover quite a bit of ground.
Then they decided to salvage the team and made flutter with it - the technical reasons of chosing it over JS sound extremely unconvincing. And the language is as you say the worst of both worlds - verbose and weak type system (I remember getting runtime type exceptions because compiler couldn't catch a type mismatch in a ternary) and none of JS dynamism, no reflection - just boilerplate on top of boilerplate.
Worst part is the react like architecture of flutter lends itself really well to immutable state management practices but the language is so weak that any immutable library involves a ton of ugly boilerplate - and they refuse to add stuff like records to the language to ameliorate the problem.
The reason it gets me so riled up to rant is that the framework itself and the idea behind it (custom native rendering framework) has potential - but dart makes using it horrible.
Meanwhile they spent colossal effort and broke half of community packages (including a bunch of first party ones) with null safety. I'd say go for low hanging fruit first.
Because the language is so limited it's impossible to solve this via library, unlike say JavaScript.
90% of the time, it felt like simple IoC plus an app-wide singletons would have been enough for most apps-- trying to get everyone to aadopt BLoC was painful and kinda meh. It's probably just that I never developed a sufficiently big app at scale with lots of devs to see why BLoC was the best way.
That said, I'm also reminded of the Boring Flutter Development Show[2], quite possibly the best produced resource I've ever seen as an intro and ongoing guide to a piece of tech. It is excellent.
[0]: https://www.dbestech.com/tutorials/flutter-bloc-pattern-exam...
[1]: https://www.flutterclutter.dev/flutter/basics/what-is-the-bl...
[2]: https://www.youtube.com/watch?v=yr8F2S3Amas&list=PLOU2XLYxms...
The tersest write-up I have on Matrix is of the JS version, and all the demos are CodeSandbox if you want to play: https://tilton.medium.com/simplejx-aweb-un-framework-e9b59c1...
While there is surely a very delicate balance of slowly deprecating a few things, remember that the only significant productivity booster is relying on existing code (as per Brooks).
I’m fairly sure there are orders of magnitude more Java code transpiled to JS running at Google than all of their Dart codebases combined, so not sure “random compilers” are a fair description.
I know little about Dart/Flutter history, but it sounds like ClojureDart might do a lot for Flutter development if only for CLJD's stability.
I guess I am trying to understand why these two coexist, which one to learn, and how likely it is that Google will kill Dart/Flutter in the next 5-10 years.
It is all about Java, Kotlin, C, C++, Web widgets and PWAs.
I am not a big Kotlin fan, the way Android has pushed it using their Android Java as counter example instead of supporting modern Java, however as JVM language it definitely has a broader industry support than Dart.
Honestly, Flutter is an amazing framework conceptually, but Dart may prove to be its demise. I just hope there is a possibility for Flutter based on Typescript or Kotlin in the future.
cough Well, this article _is_ about a delightful Lispy alternative to Dart that compiles to Dart, yielding a superior language with Genuine Dart Inside(tm) and elegant support of Flutter.
Dart may end up living on inside ClojureDart, much like DOS living on deep inside Windows and PCs.