4 ms·

TodoMVC in Rust

76 points by dumindunuwan 11y ago

mtgx 11y ago
Looks fast.
tinco 11y ago
Would be cool if there was some small web framework you could use so you could avoid having your state in RC(RefCell)'s. Perhaps it's the Haskell guy in me but I always try to make my code have zero RC or even RefCells. I'm also a complete rust noobie, so perhaps that's not good practice at all :)
- timcameronryan 11y ago
  I'd love to refactor this to not need RC's for DOM nodes. I'm new to Rust, but I expect there's a ton of room for refactoring.
xiaoma 11y ago
Where's the code?
- the_mitsuhiko 11y ago
  https://github.com/tcr/rust-todomvc https://github.com/tcr/rust-todomvc
girvo 11y ago
For something compiled with Emscripten, this was stupid quick to startup. Wow.
- flohofwoe 11y ago
  I had to check and the generated .js file is 248kByte compressed, 787kByte uncompressed. That's in the same ballpark as a comparable C++ demo, looking at the code it is even a bit big (e.g. my emscripten demos here are between 100kByte and 500kbyte: http://floooh.github.io/oryol/ http://floooh.github.io/oryol/). There is some inherent size overhead because the linked parts of the C runtime library and C++ std lib are part of the emscripten-generated JS (std::iostream and printf seem to be the biggest offenders on the C++ and C side) while on some native platforms this code lives in DLLs, but gzipped asm.js code itself isn't bigger than its gzipped 'native equivalent' (usually within +/- 10%). It is easy to created bloated code with emscripten, especially when using C++ instead of C, but for the same reasons the code would also be bloated as native executable (e.g. massive use of template and inline code).
- timcameronryan 11y ago
  I was impressed too. I think the key is that it injects all of the HTML at once. Compare that to e.g. the Backbone.js implementation which uses progressive enhancement: http://todomvc.com/examples/backbone/ http://todomvc.com/examples/backbone/ The code can be optimized further with Closure Compiler, but I wonder if that decreases startup speed.
mattmanser 11y ago
I appreciate it's to demo the capacity to compile Rust to js, but that's some really nasty code. https://github.com/tcr/rust-todomvc/blob/master/src/main.rs https://github.com/tcr/rust-todomvc/blob/master/src/main.rs Why put it all in the main? Why define functions as variables? Why .parent().unwrap().parent().unwrap()?
- seivan 11y ago
  I wonder if it would looks a bit nicer with .jsx support.
  - timcameronryan 11y ago
    I can't wait for a JSX crate on Cargo.
- steveklabnik 11y ago
  > Why define functions as variables? I'm not sure what you mean here, exactly. > Why .parent().unwrap().parent().unwrap()? I'm not mega familiar with the code, but using a low-level binding to something else that has nulls often means a lot of Option, which means a lot of unwrapping. A nicer library could probably get rid of some of this.
  - valarauca1 11y ago
    >which means a lot of unwrapping .unwrap() In rust is generally a bad pattern to use. Its basically short hand for let o :Option< u64 >; let value :u64 = match o { Some( t ) => t, None => panic!() }; So if you don't met the condition, you explode. When ever you see .unwrap() in Rust just mentally switch it for /TODO add error handling */
    - steveklabnik 11y ago
      Yeah, I was just using "unwrapping" as a more general term for "extract the T out." We almost changed 'unwrap' to 'assert', but people found it a bit too weird.
alex95 11y ago
Great - You've done something that you can achieve in another language. Want a medal?
Reefersleep 11y ago
What's the development process like for a Rust-in-the-browser project like this? I mean, is it like; write some Rust - manually start a compile process - wait a while - view result in browser - repeat? Are there nice tools? :) I'm used to working with raw JavaScript, ClojureScript with Figwheel, and Java/xhtml with JSF. Of the three, ClojureScript/Figwheel has given me the smoothest process so far, though I know there are tools for autoreloading raw js as well, just haven't gotten around to using them.
- steveklabnik 11y ago
  The general workflow with Rust is $ git clone <foo> $ cd <foo> $ cargo run With something like this, you might want to also use https://github.com/passcod/cargo-watch https://github.com/passcod/cargo-watch , which, after installing it, changes that last line to $ cargo watch and then it will recompile when you change a file, automatically. I haven't been able to test that this project works exactly this way because it looks like they're on an older nightly than I have on my machine, but it looks like that's all you need.
  - brson 11y ago
    I will be amazed if true! Last time I looked at the emscripten-Rust stack it was a tower of hacks and required a custom-hacked standard library. If that's all abstracted behind cargo build scripts that's awesome, but we're still a ways from having this be elegantly integrated into the Rust system. It's going to improve rapidly though.
    - steveklabnik 11y ago
      I think it's gotten better due to recent LLVM changes in emscripten, last I heard, but maybe maybe not. Can't wait until it's just trivial.
- timcameronryan 11y ago
  This uses a deeply hacked Rust stack. Take a look at this: https://github.com/tcr/rust-webplatform/blob/master/setup.sh https://github.com/tcr/rust-webplatform/blob/master/setup.sh It's also using a version of Rust that's pre-1.0.0. Progress is being made on making this first class though: https://github.com/rust-lang/rfcs/issues/604 https://github.com/rust-lang/rfcs/issues/604
aikah 11y ago
Nice. Maybe that can be one good use case for the use of rust. Using it in place of C++ for Emscripten. I wonder what are the other languages supported.

76 points by dumindunuwan 11y ago

mtgx 11y ago

Looks fast.

tinco 11y ago

Would be cool if there was some small web framework you could use so you could avoid having your state in RC(RefCell)'s. Perhaps it's the Haskell guy in me but I always try to make my code have zero RC or even RefCells. I'm also a complete rust noobie, so perhaps that's not good practice at all :)

timcameronryan 11y ago
I'd love to refactor this to not need RC's for DOM nodes. I'm new to Rust, but I expect there's a ton of room for refactoring.

xiaoma 11y ago

Where's the code?

the_mitsuhiko 11y ago
https://github.com/tcr/rust-todomvc https://github.com/tcr/rust-todomvc

girvo 11y ago

For something compiled with Emscripten, this was stupid quick to startup. Wow.

flohofwoe 11y ago
I had to check and the generated .js file is 248kByte compressed, 787kByte uncompressed. That's in the same ballpark as a comparable C++ demo, looking at the code it is even a bit big (e.g. my emscripten demos here are between 100kByte and 500kbyte: http://floooh.github.io/oryol/ http://floooh.github.io/oryol/). There is some inherent size overhead because the linked parts of the C runtime library and C++ std lib are part of the emscripten-generated JS (std::iostream and printf seem to be the biggest offenders on the C++ and C side) while on some native platforms this code lives in DLLs, but gzipped asm.js code itself isn't bigger than its gzipped 'native equivalent' (usually within +/- 10%). It is easy to created bloated code with emscripten, especially when using C++ instead of C, but for the same reasons the code would also be bloated as native executable (e.g. massive use of template and inline code).
timcameronryan 11y ago
I was impressed too. I think the key is that it injects all of the HTML at once. Compare that to e.g. the Backbone.js implementation which uses progressive enhancement: http://todomvc.com/examples/backbone/ http://todomvc.com/examples/backbone/ The code can be optimized further with Closure Compiler, but I wonder if that decreases startup speed.

mattmanser 11y ago

I appreciate it's to demo the capacity to compile Rust to js, but that's some really nasty code. https://github.com/tcr/rust-todomvc/blob/master/src/main.rs https://github.com/tcr/rust-todomvc/blob/master/src/main.rs Why put it all in the main? Why define functions as variables? Why .parent().unwrap().parent().unwrap()?

seivan 11y ago
I wonder if it would looks a bit nicer with .jsx support.
- timcameronryan 11y ago
  I can't wait for a JSX crate on Cargo.
steveklabnik 11y ago
> Why define functions as variables? I'm not sure what you mean here, exactly. > Why .parent().unwrap().parent().unwrap()? I'm not mega familiar with the code, but using a low-level binding to something else that has nulls often means a lot of Option, which means a lot of unwrapping. A nicer library could probably get rid of some of this.
- valarauca1 11y ago
  >which means a lot of unwrapping .unwrap() In rust is generally a bad pattern to use. Its basically short hand for let o :Option< u64 >; let value :u64 = match o { Some( t ) => t, None => panic!() }; So if you don't met the condition, you explode. When ever you see .unwrap() in Rust just mentally switch it for /TODO add error handling */
  - steveklabnik 11y ago
    Yeah, I was just using "unwrapping" as a more general term for "extract the T out." We almost changed 'unwrap' to 'assert', but people found it a bit too weird.

alex95 11y ago

Great - You've done something that you can achieve in another language. Want a medal?

Reefersleep 11y ago

What's the development process like for a Rust-in-the-browser project like this? I mean, is it like; write some Rust - manually start a compile process - wait a while - view result in browser - repeat? Are there nice tools? :) I'm used to working with raw JavaScript, ClojureScript with Figwheel, and Java/xhtml with JSF. Of the three, ClojureScript/Figwheel has given me the smoothest process so far, though I know there are tools for autoreloading raw js as well, just haven't gotten around to using them.

steveklabnik 11y ago
The general workflow with Rust is $ git clone <foo> $ cd <foo> $ cargo run With something like this, you might want to also use https://github.com/passcod/cargo-watch https://github.com/passcod/cargo-watch , which, after installing it, changes that last line to $ cargo watch and then it will recompile when you change a file, automatically. I haven't been able to test that this project works exactly this way because it looks like they're on an older nightly than I have on my machine, but it looks like that's all you need.
- brson 11y ago
  I will be amazed if true! Last time I looked at the emscripten-Rust stack it was a tower of hacks and required a custom-hacked standard library. If that's all abstracted behind cargo build scripts that's awesome, but we're still a ways from having this be elegantly integrated into the Rust system. It's going to improve rapidly though.
  - steveklabnik 11y ago
    I think it's gotten better due to recent LLVM changes in emscripten, last I heard, but maybe maybe not. Can't wait until it's just trivial.
timcameronryan 11y ago
This uses a deeply hacked Rust stack. Take a look at this: https://github.com/tcr/rust-webplatform/blob/master/setup.sh https://github.com/tcr/rust-webplatform/blob/master/setup.sh It's also using a version of Rust that's pre-1.0.0. Progress is being made on making this first class though: https://github.com/rust-lang/rfcs/issues/604 https://github.com/rust-lang/rfcs/issues/604

aikah 11y ago

Nice. Maybe that can be one good use case for the use of rust. Using it in place of C++ for Emscripten. I wonder what are the other languages supported.