A sample Python project to demonstrate basic type checking concepts and best practices.
The four sample projects included correspond to each section of the PyCon 2022 "Python Types for Fun and Profit" tutorial.
introduction_exercises: Annotating examples of basic data structures.demo_project: Getting-started demo for setting up Pyre locally in a new project.gradual_typing_project: Example project for applying type checking modes and other approaches to gradually increasing type coverage.typing_pattern_exercises: More detailed and advanced Python patterns to practice expressing dynamic behavior in the type system
You'll want a python 3.10 environment and watchman, along with the
latest version of the pyre-check package.
If you run into trouble, an alternative way to get started is to sign up
for repl.it (you can sign in through github) and use
the PyrePycon2022 repl
to try out Pyre on Linux in the browser.
Watchman is a file monitoring service that records when files change. It is required to run a type checker server that delivers fast, incremental results based on file updates. Without it, you will need to run a full pyre check that type checks the entire project each time and cannot use editor integration.
brew install watchmansudo apt-get update
sudo apt-get -y watchmanHow exactly to get the latest Python release varies system to system,
and you may already use a solution such as conda.
We have instructions for using pyenv for this, but you're welcome
to use any other approach you know.
brew install pyenv
echo '
export PYENV_ROOT="$HOME/.pyenv"
export PATH="$PYENV_ROOT/bin:$PATH"
export PATH="$PYENV_ROOT/shims:$PATH"
eval "$(pyenv init -)"
' >> ~/.profile
. ~/.profile
pyenv install 3.10.4sudo apt-get update
sudo apt-get install -y \
git make build-essential libssl-dev zlib1g-dev libbz2-dev \
libreadline-dev libsqlite3-dev wget curl llvm libncurses5-dev \
libncursesw5-dev xz-utils tk-dev libffi-dev liblzma-dev
git clone https://github.com/pyenv/pyenv.git ~/.pyenv
echo '
export PYENV_ROOT="$HOME/.pyenv"
export PATH="$PYENV_ROOT/bin:$PATH"
export PATH="$PYENV_ROOT/shims:$PATH"
eval "$(pyenv init -)"
' >> ~/.profile
. ~/.profile
pyenv install 3.10.4We recommend using the Windows Subsystem for Linux:
- Open a windows console in administrator mode
- Run
wsl --install -d Ubuntu-20.04 - Restart your computer
- When it restarts, the
Ubuntu-20.04application should open- Create a user. We recommend reusing the user from your windows install, but you could create a user just for pycon
- Now, follow the
Ubuntuinstructions above.
From this point forward, to work with pyre you can:
- Open the
Ubuntu-20.04application - Do any terminal actions (like running
pyre) you want from that terminal session. - In order to use native tools, like your (VSCode editor) with
files here, run
explorer.exe <name_of_a_directory>- This will open up the directory in windows explorer.
- From there you can do things like open files in VSCode.
You can clone this repo in one of two ways:
- First fork it to your user using the "Fork" button, and then clone from that repository
- Or, if you don't care about playing with github, just clone directly:
git clone https://github.com/fbsamples/python-typing-tutorial.git
Then, set it up to use Python 3.10.4:
cd python-typing-tutorial
PYENV_VERSION=3.10.4 python -m venv pyre-venv
. pyre-venv/bin/activate
pip install pyre-check
You can make sure it works by running
cd gradual_typing_project
pyre init <<< '
'
pyre
which should spit out:
+ No type errors found
See the CONTRIBUTING file for how to help out.
python-typing-tutorial is MIT licensed, as found in the LICENSE file.