Yeah, I'm just trying to point out, that not much would be won by that.

You either need to change the semantic of the language (CPython) or live with a slow JIT for some of the most used features of the language... And changing the semantic of the language is pretty terrible - it fragments your libraries introduces unbreakable borders prohibiting cross package optimizations and extensability, and much worse, CPython is now basically a language that combines the bad stuff of python and C ;) I know, that's a bit too cynical, but coming from a well designed language for JIT (Julia), that's how CPython starts looking to me. You will simply never reach the elegance of a language that was designed from scratch for this.

What I want to point out is, that the whole topic is bigger than "JIT my one slow function and make it fast"! A good read about this topic is: http://www.stochasticlifestyle.com/why-numba-and-cython-are-...

And sorry for hijacking your perfectly fine comment - of course it would help python to embrace modern compiler technologies! ;) It's just always a bit maddening to see how much effort and money is spent on creating imense projects for python, just to catch up with Julia - while turning python pretty much into a jitted frankenstein monster, to cover use cases it was never designed for ;)