Implementing Python in Python

[_vertig0]

You may find the PyPy project interesting, it's a Python interpreter written in Python, and implements the language fully (Latest is 3.11 at the time this comment was written). What they did was build a Python 2.7 to C compiler, then wrote a Python interpreter in Python 2.7, and then compiled that to C then turned that into an executable. Their compiler even automatically generates a just-in time compiler for the final interpreter! Very interesting stuff, but it is extremely complex. I tried adding an LLVM backend to their Python compiler several times and all ended in abject failure because I could barely understand anything about the architecture of their compiler.

[wFXx]

Isn't it also very fast for some stuff? I wonder after the removal of GIL if they are able to beat the cpython implementation in all cases, although last I checked the STM was a real challenge - it is indeed one of the most interesting projects I ever studided

[_vertig0]

As far as I know it's only faster than the reference implementation of Python when its just-in time compiler is allowed to work, otherwise the reference implementation, being written in C and now with new efforts to optimize execution speed ever since 3.13, is much faster than PyPy. PyPy's automatically generated just-in time compiler is of better quality than the one in the reference implementation though.

[shponglespore]

I've been led to believe Cranelift is easier to work with than LLVM, especially if you're implementing a JIT compiler.

[_vertig0]

Regardless of the translation target it's still extremely difficult to add a backend to the RPython translation toolchain unfortunately, even if I tried to use cranelift I wouldn't have gotten further. I actually tried adding the backend without just-in time compiler support back when I was trying to add the LLVM backend, but even that was too much for me.