mypy
pyright
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mypy | pyright | |
---|---|---|
112 | 135 | |
17,410 | 11,846 | |
1.8% | 2.9% | |
9.8 | 9.8 | |
about 14 hours ago | 7 days ago | |
Python | Python | |
GNU General Public License v3.0 or later | GNU General Public License v3.0 or later |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
mypy
- The GIL can now be disabled in Python's main branch
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Polars – A bird's eye view of Polars
It's got type annotations and mypy has a discussion about it here as well: https://github.com/python/mypy/issues/1282
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Python 3.13 Gets a JIT
There is already an AOT compiler for Python: Nuitka[0]. But I don't think it's much faster.
And then there is mypyc[1] which uses mypy's static type annotations but is only slightly faster.
And various other compilers like Numba and Cython that work with specialized dialects of Python to achieve better results, but then it's not quite Python anymore.
- Introducing Flask-Muck: How To Build a Comprehensive Flask REST API in 5 Minutes
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It's Time for a Change: Datetime.utcnow() Is Now Deprecated
It's funny you should say this.
Reading this article prompted me to future-proof a program I maintain for fun that deals with time; it had one use of utcnow, which I fixed.
And then I tripped over a runtime type problem in an unrelated area of the code, despite the code being green under "mypy --strict". (and "100% coverage" from tests, except this particular exception only occured in a "# pragma: no-cover" codepath so it wasn't actually covered)
It turns out that because of some core decisions about how datetime objects work, `datetime.date.today() < datetime.datetime.now()` type-checks but gives a TypeError at runtime. Oops. (cause discussed at length in https://github.com/python/mypy/issues/9015 but without action for 3 years)
One solution is apparently to use `datetype` for type annotations (while continuing to use `datetime` objects at runtime): https://github.com/glyph/DateType
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What's New in Python 3.12
PEP 695 is great. I've been using mypy every day at work in last couple years or so with very strict parameters (no any type etc) and I have experience writing real life programs with Rust, Agda, and some Haskell before, so I'm familiar with strict type systems. I'm sure many will disagree with me but these are my very honest opinions as a professional who uses Python types every day:
* Some types are better than no types. I love Python types, and I consider them required. Even if they're not type-checked they're better than no types. If they're type-checked it's even better. If things are typed properly (no any etc) and type-checked that's even better. And so on...
* Having said this, Python's type system as checked by mypy feels like a toy type system. It's very easy to fool it, and you need to be careful so that type-checking actually fails badly formed programs.
* The biggest issue I face are exceptions. Community discussed this many times [1] [2] and the overall consensus is to not check exceptions. I personally disagree as if you have a Python program that's meticulously typed and type-checked exceptions still cause bad states and since Python code uses exceptions liberally, it's pretty easy to accidentally go to a bad state. E.g. in the linked github issue JukkaL (developer) claims checking things like "KeyError" will create too many false positives, I strongly disagree. If a function can realistically raise a "KeyError" the program should be properly written to accept this at some level otherwise something that returns type T but 0.01% of the time raises "KeyError" should actually be typed "Raises[T, KeyError]".
* PEP 695 will help because typing things particularly is very helpful. Often you want to pass bunch of Ts around but since this is impractical some devs resort to passing "dict[str, Any]"s around and thus things type-check but you still get "KeyError" left and right. It's better to have "SomeStructure[T]" types with "T" as your custom data type (whether dataclass, or pydantic, or traditional class) so that type system has more opportunities to reject bad programs.
* Overall, I'm personally very optimistic about the future of types in Python!
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Mypy 1.6 Released
# is fixed: https://github.com/python/mypy/issues/12987.
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Ask HN: Why are all of the best back end web frameworks dynamically typed?
You probably already know but you can add type hints and then check for consistency with https://github.com/python/mypy in python.
Modern Python with things like https://learnpython.com/blog/python-match-case-statement/ + mypy + Ruff for linting https://github.com/astral-sh/ruff can get pretty good results.
I found typed dataclasses (https://docs.python.org/3/library/dataclasses.html) in python using mypy to give me really high confidence when building data representations.
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Sharing Saturday #472
The in-progress tutorial is here in the official documentation. It sucks that I can never seem to make quick progress on this. Trying to do something clever with Protocols ended up with me making a pull request on the Mypy project for something that likely wasn't critical after all.
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Writing Python like it's Rust
I'm also 100% convinced most people who use mypy don't realize the myriad ways it just silently stopps typing things or just silently crashes with a 0 exit code. Even if you configure it to warn untyped functions etc. It will still just not work properly in some of circumstances and you will literally never know until you debug a bug that just happened to trigger it. There are over 1.4k open but tickets it's such a broken piece of software: https://github.com/python/mypy/issues?q=is%3Aissue+is%3Aopen...
The involvement of Guido in mypy is such a tragedy.
pyright
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Enhance Your Project Quality with These Top Python Libraries
Pyright is a fast type checker meant for large Python source bases. It can run in a “watch” mode and performs fast incremental updates when files are modified.
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Mypy 1.6 Released
Not exactly what you are looking for but maybe useful to others.
https://github.com/microsoft/pyright/blob/main/docs/mypy-com...
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VSCodium – Libre Open Source Software Binaries of VS Code
You can use pyright instead[0]. It is the FOSS version of pyright, but having some features missing.
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How do you enable semantic highlighting for Python?
Unfortunately, pyright explicitly stated that they are not interested in inlay hints or other language server features, that those will only be added to pylance. That's why I added it myself instead of submitting a pull request to pyright. See https://github.com/microsoft/pyright/issues/4325
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How do I enable an LSP for json files?
return { -- add pyright to lspconfig { "neovim/nvim-lspconfig", ---@class PluginLspOpts opts = { ---@type lspconfig.options servers = { -- Listed servers will be automatically loaded to buffers jsonls = { settings = { json = { format = { enable = true, }, }, validate = { enable = true }, }, }, pyright = { settings = { python = { analysis = { -- https://github.com/microsoft/pyright/blob/main/docs/settings.md autoSearchPaths = false, useLibraryCodeForTypes = true, diagnosticMode = "openFilesOnly", }, }, }, }, }, -- Add folding capability to use LSP for ufo plugin capabilities = { textDocument = { foldingRange = { dynamicRegistration = false, lineFoldingOnly = true, }, }, }, }, }, }
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Pyright does not respect virtualenv (astronvim)
I don't use astro, but you can configure pyright by using a pyrightconfig.json or directly in the LSP configuration.
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Eglot + pyright can not get completion on django.db.models
Not sure if pyright supports it unfortunately. I personally accepted the lack of support for attr.s and can't tell what the status on this actually is today. Here's a link to start reading up on the issue https://github.com/Microsoft/pyright/issues/146
- [Neovim] Quel Python LSP est le meilleur?
- [Neovim] ¿Qué Python LSP es mejor?
What are some alternatives?
jedi-language-server - A Python language server exclusively for Jedi. If Jedi supports it well, this language server should too.
python-lsp-server - Fork of the python-language-server project, maintained by the Spyder IDE team and the community
python-language-server - Microsoft Language Server for Python
coc-jedi - coc.nvim wrapper for https://github.com/pappasam/jedi-language-server
pylance-release - Documentation and issues for Pylance
ruff - An extremely fast Python linter and code formatter, written in Rust.
flake8
pyre-check - Performant type-checking for python.
black - The uncompromising Python code formatter
pytype - A static type analyzer for Python code