6 ms·

Rusthon – A Pythonic language that compiles to Rust and C++

139 points by doublextremevil 12y ago

sdfjkl 12y ago
Reminds me of Nim (formerly Nimrod): http://nim-lang.org/ http://nim-lang.org/
- def- 12y ago
  Nim was also in the benchmark on the frontpage yesterday: https://news.ycombinator.com/item?id=8778041 https://news.ycombinator.com/item?id=8778041
deleted 12y ago
[deleted]
haberman 12y ago
Compiling to Rust is a really interesting proposition, because it means the resulting program has the same safe-without-gc properties as native Rust programs.
- quotemstr 12y ago
  Unless it transmutes pointers and uses unsafe blocks, of course. One of Rust's most important features is that you can do things like that. Hell, the stdlib even has longjmp.
  - tomjakubowski 12y ago
    Really? Where's the longjmp function?
    - quotemstr 12y ago
      Err, I think I was mistaken.
  - alkonaut 12y ago
    Surely it just does that, otherwise it would be dropping all the cognitive overhead of lifetime management that we pay (happily) in Rust, without losing safety? If that was possible you'd think it was already in the Rust specs...
jumanji 12y ago
https://github.com/rusthon/Rusthon/blob/master/pythonjs/translator.py#L32 https://github.com/rusthon/Rusthon/blob/master/pythonjs/tran... if '--cpp' [...] rust=True Is that a bug?
- throwaway_99837 12y ago
  `python_to_pythonjs` seems to ignore that flag.
- broodbucket 12y ago
  https://github.com/rusthon/Rusthon/blob/master/pythonjs/python_to_pythonjs.py#L154 https://github.com/rusthon/Rusthon/blob/master/pythonjs/pyth... Doesn't look like there's C++ flag in python_to_pythonjs, so I'd guess not.
amit_m 12y ago
Cython already compiles to C and is relatively mature. In my opinion these hacks will always be specialty tools. What the world really needs is more languages that are both expressive and run pretty fast. e.g. Julia.
- deleted 12y ago
  [deleted]
- shadowmint 12y ago
  Cython isn't the answer. It's a neat tool, for sure, but it's a very specific thing, and it has several down sides, mainly: - Every module compiles to a shared library. - Requires significant c infrastructure installed on the target machine to compile. - Compiled code cannot be used without the python runtime. This renders it almost useless for generating code for serious applications. It's an adhoc solution to ffi and slowness because those are things are major issues for python. However, this (Rusthon) has some serious upsides: The transpiled (if that's the word?) C++ / rust code is portable and fast. It does not include the bloated standard python library. It can be directly compiled using existing compiler tools for mobile devices (to be fair, as the kivy-ios project shows, this isn't impossible with cython, but it involves patching the python source to load modules differently).
  - andreasvc 12y ago
    > - Every module compiles to a shared library. How else would you import a module if it wasn't? If you want to reduce the number of shared libraries you could put all your code in a single module, of course. > - Requires significant c infrastructure installed on the target machine to compile. Anything which involves compilation to native code requires significant infrastructure. > - Compiled code cannot be used without the python runtime. And this is a downside why? Combining the best of both worlds--native code and Python--is the whole point. If you want to take out Python from the equation just use C/C++.
    - shadowmint 12y ago
      The issues I pointed out are related to building distributable targets. Shared library per module and 'wrapped' compiler execution for example, is fundamentally hostile to distribution for mobile environments. Have a look at the hoops kivy-ios jumps though. It's absolutely ridiculous. That's the thing python is the worst at; building a single stand alone application that does not require the user to install a copy of python and run pip to download a million dependencies before it will run. This isn't in question. It's just life; that's not what python is good at. Cython doesn't solve that problem. It solves a different set of problems; namely, ffi and speed. My point is that by choosing an alternative approach (compile to portable C++ / rust) this project gives you the benefits of ffi and speed and distribution.
duey 12y ago
Why would you use this over LLVM? e.g. pyston (LLVM Python) and then using llc -march=rustc/c/cpp/whatever to convert?
- rattray 12y ago
  Pyston is a very exciting project. The commit velocity on github seems quite high [0]. Here's the latest status update on their blog, for those interested: http://blog.pyston.org/2014/11/21/pyston-status-update/ http://blog.pyston.org/2014/11/21/pyston-status-update/ [0] https://github.com/dropbox/pyston/graphs/commit-activity https://github.com/dropbox/pyston/graphs/commit-activity
  - techdragon 12y ago
    Except it's not targeting Python 3 Pypy is pushing towards full 3.4 slowly, which is good because I want some of that Juicy STM support in my web apps.
    - BuckRogers 12y ago
      You are one of few concerned with Python3 targets. Pyston, PyPy are all mostly Python(2) projects. PyPy3 does exist, but it's considered beta and not recommended for production use as PyPy is. Python(2) code/libraries will mainly survive on PyPy/Pyston going forward. With stuff like Nim and Rusthon, I think something like those will carry the torch forward after Python(2), rather than Python3.
- yazaddaruvala 12y ago
  The biggest reason would be the "native" interoperability. No FFIs because while you could call it a language it's more accurately syntax sugar. Another reason with Rust at least. Rusthon can make the same memory guarantees as Rust. Personally I wish this was done with Ruby.. But then again I'm not writing it myself, so I can't really complain. A random last thought, it would be really something if Rust could formally prove its memory safety and then push that whole system of lifetimes and borrow checks into LLVM or a similar abstraction on top of LLVM. Because Rust as a compiler target is very interesting but it wasn't really built for that.
Demiurge 12y ago
As I'm sure everyone, I was wondering, why... If you follow through from the top to the blog, there is authors reasoning: Introducing Rusthon Rust is a systems programming language, and too low level for quick prototyping, or simple web backends. It is nice to have all of the low level control so you can fine tune performance later, but it should be optional. Rusthon is a high level Python-like language that compiles to Rust. Rusthon started as a fork of Gython, which is a fork of PythonJS. The goal of Rusthon is simple and clean syntax inspired by Python. Rusthon will allow you to code at a higher level than normal Rust code, and interoperate well with hand written Rust and the Rust libraries. You can start off writting your application in Rusthon, and drop down to hand written Rust where you need more performance. http://rusthon-lang.blogspot.com/ http://rusthon-lang.blogspot.com/
lago 12y ago
# naming fix :) mv Rusthon Pythrust
chenzhekl 12y ago
It would be great if it can interoperate seamlessly with existed C++ library.
Matthias247 12y ago
Does this care about memory at all? In the transpiled code I see structures getting allocated but never deallocated. That will work for this trivial examples, but not for anything serious. To properly translate Python to C++ you would have atleast produce a shared_ptr<T> from every T and even that doesn't work with cycles. Rust translation is even more complicated.
- agentultra 12y ago
  It also doesn't even appear to generator initializer lists for the constructor which could lead to some fun behaviors down the road...
andywood 12y ago
Some comments here suggest the possibility of making manual changes to the Rust code. After cross compiling, how does one make changes to the Rust code, then go back and make changes to the Python code, and cross compile again without losing the customized Rust code?

sdfjkl 12y ago

Reminds me of Nim (formerly Nimrod): http://nim-lang.org/ http://nim-lang.org/

def- 12y ago
Nim was also in the benchmark on the frontpage yesterday: https://news.ycombinator.com/item?id=8778041 https://news.ycombinator.com/item?id=8778041

deleted 12y ago

[deleted]

haberman 12y ago

Compiling to Rust is a really interesting proposition, because it means the resulting program has the same safe-without-gc properties as native Rust programs.

quotemstr 12y ago
Unless it transmutes pointers and uses unsafe blocks, of course. One of Rust's most important features is that you can do things like that. Hell, the stdlib even has longjmp.
- tomjakubowski 12y ago
  Really? Where's the longjmp function?
  - quotemstr 12y ago
    Err, I think I was mistaken.
- alkonaut 12y ago
  Surely it just does that, otherwise it would be dropping all the cognitive overhead of lifetime management that we pay (happily) in Rust, without losing safety? If that was possible you'd think it was already in the Rust specs...

jumanji 12y ago

https://github.com/rusthon/Rusthon/blob/master/pythonjs/translator.py#L32 https://github.com/rusthon/Rusthon/blob/master/pythonjs/tran... if '--cpp' [...] rust=True Is that a bug?

throwaway_99837 12y ago
`python_to_pythonjs` seems to ignore that flag.
broodbucket 12y ago
https://github.com/rusthon/Rusthon/blob/master/pythonjs/python_to_pythonjs.py#L154 https://github.com/rusthon/Rusthon/blob/master/pythonjs/pyth... Doesn't look like there's C++ flag in python_to_pythonjs, so I'd guess not.

amit_m 12y ago

Cython already compiles to C and is relatively mature. In my opinion these hacks will always be specialty tools. What the world really needs is more languages that are both expressive and run pretty fast. e.g. Julia.

deleted 12y ago
[deleted]
shadowmint 12y ago
Cython isn't the answer. It's a neat tool, for sure, but it's a very specific thing, and it has several down sides, mainly: - Every module compiles to a shared library. - Requires significant c infrastructure installed on the target machine to compile. - Compiled code cannot be used without the python runtime. This renders it almost useless for generating code for serious applications. It's an adhoc solution to ffi and slowness because those are things are major issues for python. However, this (Rusthon) has some serious upsides: The transpiled (if that's the word?) C++ / rust code is portable and fast. It does not include the bloated standard python library. It can be directly compiled using existing compiler tools for mobile devices (to be fair, as the kivy-ios project shows, this isn't impossible with cython, but it involves patching the python source to load modules differently).
- andreasvc 12y ago
  > - Every module compiles to a shared library. How else would you import a module if it wasn't? If you want to reduce the number of shared libraries you could put all your code in a single module, of course. > - Requires significant c infrastructure installed on the target machine to compile. Anything which involves compilation to native code requires significant infrastructure. > - Compiled code cannot be used without the python runtime. And this is a downside why? Combining the best of both worlds--native code and Python--is the whole point. If you want to take out Python from the equation just use C/C++.
  - shadowmint 12y ago
    The issues I pointed out are related to building distributable targets. Shared library per module and 'wrapped' compiler execution for example, is fundamentally hostile to distribution for mobile environments. Have a look at the hoops kivy-ios jumps though. It's absolutely ridiculous. That's the thing python is the worst at; building a single stand alone application that does not require the user to install a copy of python and run pip to download a million dependencies before it will run. This isn't in question. It's just life; that's not what python is good at. Cython doesn't solve that problem. It solves a different set of problems; namely, ffi and speed. My point is that by choosing an alternative approach (compile to portable C++ / rust) this project gives you the benefits of ffi and speed and distribution.

duey 12y ago

Why would you use this over LLVM? e.g. pyston (LLVM Python) and then using llc -march=rustc/c/cpp/whatever to convert?

rattray 12y ago
Pyston is a very exciting project. The commit velocity on github seems quite high [0]. Here's the latest status update on their blog, for those interested: http://blog.pyston.org/2014/11/21/pyston-status-update/ http://blog.pyston.org/2014/11/21/pyston-status-update/ [0] https://github.com/dropbox/pyston/graphs/commit-activity https://github.com/dropbox/pyston/graphs/commit-activity
- techdragon 12y ago
  Except it's not targeting Python 3 Pypy is pushing towards full 3.4 slowly, which is good because I want some of that Juicy STM support in my web apps.
  - BuckRogers 12y ago
    You are one of few concerned with Python3 targets. Pyston, PyPy are all mostly Python(2) projects. PyPy3 does exist, but it's considered beta and not recommended for production use as PyPy is. Python(2) code/libraries will mainly survive on PyPy/Pyston going forward. With stuff like Nim and Rusthon, I think something like those will carry the torch forward after Python(2), rather than Python3.
yazaddaruvala 12y ago
The biggest reason would be the "native" interoperability. No FFIs because while you could call it a language it's more accurately syntax sugar. Another reason with Rust at least. Rusthon can make the same memory guarantees as Rust. Personally I wish this was done with Ruby.. But then again I'm not writing it myself, so I can't really complain. A random last thought, it would be really something if Rust could formally prove its memory safety and then push that whole system of lifetimes and borrow checks into LLVM or a similar abstraction on top of LLVM. Because Rust as a compiler target is very interesting but it wasn't really built for that.

Demiurge 12y ago

As I'm sure everyone, I was wondering, why... If you follow through from the top to the blog, there is authors reasoning: Introducing Rusthon Rust is a systems programming language, and too low level for quick prototyping, or simple web backends. It is nice to have all of the low level control so you can fine tune performance later, but it should be optional. Rusthon is a high level Python-like language that compiles to Rust. Rusthon started as a fork of Gython, which is a fork of PythonJS. The goal of Rusthon is simple and clean syntax inspired by Python. Rusthon will allow you to code at a higher level than normal Rust code, and interoperate well with hand written Rust and the Rust libraries. You can start off writting your application in Rusthon, and drop down to hand written Rust where you need more performance. http://rusthon-lang.blogspot.com/ http://rusthon-lang.blogspot.com/

lago 12y ago

# naming fix :) mv Rusthon Pythrust

chenzhekl 12y ago

It would be great if it can interoperate seamlessly with existed C++ library.

Matthias247 12y ago

Does this care about memory at all? In the transpiled code I see structures getting allocated but never deallocated. That will work for this trivial examples, but not for anything serious. To properly translate Python to C++ you would have atleast produce a shared_ptr<T> from every T and even that doesn't work with cycles. Rust translation is even more complicated.

agentultra 12y ago
It also doesn't even appear to generator initializer lists for the constructor which could lead to some fun behaviors down the road...

andywood 12y ago

Some comments here suggest the possibility of making manual changes to the Rust code. After cross compiling, how does one make changes to the Rust code, then go back and make changes to the Python code, and cross compile again without losing the customized Rust code?