[Groxx]

Is the claim that pypy has no spec, but cpython does? By that definition I think either both have a spec (they both use https://docs.python.org/3/reference/index.html and both are just "an implementation") or neither has one (since neither fully specifies all behavior and all modules, which is probably true for ~all languages).

[toolslive]

No. The claim is cpython has no spec. The link you posted is about the language. The spec claim is about the behaviour of the runtime.

The underlying claim is hat pypy cannot succeed precisely because there's no clear definition of success/compatibility/compliance. The situation is completely different in the Java world. There there is a specification for the memory model, runtime, aso and you can be sure that when you switch between runtimes, it will just work.

[Groxx]

Gotcha. Broadly agreed then (Java is a very good counter-example), though I think pypy might be succeeding quite a bit more than org-mode in terms of users... and org-mode doesn't have a language spec either afaict. It has a fairly good description of the current code's parsing behavior, but the closest I've seen to something rigorous is https://github.com/200ok-ch/org-parser and even that's still unfinished from the readme (and it seems probably abandoned).

I haven't looked into the actual current state of things though, my last check was a couple years ago. I'd be pretty happy if things have changed, I just haven't seen any sign of that.