pyre-check VS typing

Facebook/Instagram uses Pyre which is a typechecker for Python.

I'd be curious if the pyre-check compilation is any faster for you either by removing the inlining optimization flag (the `-Oclassic` here https://github.com/facebook/pyre-check/blame/36243764ab81a82...) or whether there's a way to compile pyre-check to bytecode instead of the native compilation step (which unfortunately it looks like there's no easy way to modify pyre-check's build config to do so).

I must be doing something wrong.

[1] https://github.com/facebook/pyre-check

Some other good alternatives for type checking are Pyright (which is seen in VSCode via Microsofts PyLance plugin) and Pyre.

Sorry if this is something that you’re already aware of but there already exists a Python-related project with the same name which may lead to confusion. https://pyre-check.org

See https://github.com/python/typing/issues/256 for a discussion.

Lower bounds are not supported for TypeVars, unfortunately.

Mypy allows that because initial versions of PEP-484 allowed that. This has changed; here's the current wording on the PEP:

> This is no longer the recommended behavior. Type checkers should move towards requiring the optional type to be made explicit.

https://www.python.org/dev/peps/pep-0484/#id29

Dunno, other, larger projects than the one I'm working on seem to run up against this from time to time. (rasa_core, to pick one example from near the top of a Google search; also Telethon, Blender, TensorFlow, Pandas. Guido also filed a bug on the typing module in an early version of Python 3.5 because of unexpected implications of this particular issue, so the problem isn't exactly purely theoretical.) That's aside from the wish for conceptual purity in the call signatures of classes and their subclasses, which is not always and automatically a bad wish to have; and the notion that a language that prides itself on its introspective faculties might want to make introspection of classes from the top of a class hierarchy possible, at least in theory? Perhaps to facility learning about the language and/or visualizing large class hierarchies easily, for instance?

Yeah it's called Type Hinting

How do you define Python? If you include PEP 484 in your definition, surely it must be 'statically typed', otherwise there would be no need for these terms.

Since Python 3.5 (PEP-484), developers can add type annotations to their code. Python's optional static typing improves code comprehension, code completion, program analysis, and more. However, retrofitting type annotations can be a laborious and time-consuming task.

https://www.python.org/dev/peps/pep-0484/#forward-references

You might be interested in looking at PEP 484 (Type Hints https://www.python.org/dev/peps/pep-0484/) and PEP 483 (The Theory of Type Hints https://www.python.org/dev/peps/pep-0483/).