Developing PyPy's Rpython as a general programming language [closed]

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Is there any interest in developing Rpython (Restricted Python) from the PyPy project as a general purpose programming language? Perhaps it could be a fork from the PyPy project. Does such a project exist? Since the programs are compiled, one could simply contribute modules written in Rpython, and it could compete with other py开发者_开发百科thon implementations including CPython and PyPy.

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I can't speak for everyone else, but I personally am extremely interested in using RPython as a general-purpose language. To answer some other people's questions:

Why? Because Cython is a pain to figure out how to use. If you don't put in a lot of tricky type declarations just right, you don't get any speedup. With RPython, it will run fast or it won't run at all.

Using PyPy offers a good speedup, but currently not nearly as much as RPython.

RPython might be a good way to get super-fast, somewhat Pythonic code. Here's an example to help you get started. I'm not aware of any large projects to do this, unfortunately.

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Yes, there is already a project to use the translation tool chain of PyPy to create standalone executables and libraries using RPython. It is called RPythonic.

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A general purpose RPython would not be a competitor for CPython and PyPy. It wouldn't even be a competitor for things like Cython.

Why? Because RPython is not Python!! RPython is merely a language which shares some syntax with Python; enough that a Python interpreter can execute RPython code, but you cannot take Python code and compile it as RPython.

The restrictions on Python that are added to enable RPython to be statically typed and compiled (indeed, to have static type inference) are so severe that they completely change the language. If you want to write an RPython program, you have to decide to do so up front and write it in RPython. You can't write a program in Python and then decide to compile it as RPython, and you can't even tweak a realistic Python program a bit to make it RPython. Normal Python code is nothing like normal RPython code; writing RPython is more similar to writing Java or C#.

So if you want to write general programs in Python but you want them to go faster, RPython has very little to offer you. That's the niche PyPy's Python interpreter is trying to fill.

If you want to write general programs in a lower level compiled language because you need your program to run faster than Python, then there are existing very mature languages and libraries for that, like Java or C#.

The reason to code in RPython would be to do something that is particularly made better by RPython. Like writing interpreters to which you can add garbage collectors and JIT compilers without having to write them by hand! Here RPython shines, and yes I would be very interested in a more polished and usable RPython interpreter-writing environment. But as a general purpose programming language for writing programs that don't particularly benefit from RPython's specialities, it would simply be a monstrous amount of work to get it to the point where it could compete with existing languages that already fill that role better. It barely even has a standard library now (because almost none of Python's extensive standard library is usable in RPython), for example.

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From the looks of it, the restrictions are quite severe and on the whole it's a lot less to program in, I imagine. That's necessary for implementing PyPy, but generally if you want fast compiled code that can interact with Python, you'd use Cython (which is targeted at CPython extensions and supports pretty much all of Python seamlessly) or write code in one of the more common languages that can do this. And if you just want fast, compiled code... well, RPython may be more pleasant than e.g. C, but still, I don't see a significant advantage here (at least none that would warrant the effort to create a usable, stable language).

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Why would I want to write directly in RPython?

It seems so much simpler to Python code and run PyPy.

Why would I want to write C code?

It seems so much simpler to write Python and have PyPy be implemented in C

Why would I want to write assembler code?

It seems so much simpler to write Python and have PyPy implemented in C and C implemented in Assembler.

I guess it really is turtles all the way down.

Why would I want to stop using the most convenient language and switch to a less convenient language?

What's the value in giving up a nice language?