LPython

LPython is a Python compiler. It is in heavy development, currently in pre-alpha stage. Some of the goals of LPython:

• The best possible performance for numerical array oriented code
• Run on all platforms
• Compile a subset of Python and be Python compatible
• Explore how to design it so that it can be eventually used with any Python code
• Fast compilation
• Excellent user friendly diagnostic messages: error, warnings, hints, notes, etc.
• Ahead of time compilation to binaries and interactive usage (Jupyter notebook)
• Able to transform the Python code to C++, Fortran and other languages

And more.

Installation

LPython works on Windows, macOS and Linux.

Install Conda

If you do not have Conda already installed, please follow the instructions here to install Conda on your platform:

https://github.com/conda-forge/miniforge/#download

Compile LPython

Install required packages (Linux - 64 bit):

sudo apt install binutils-dev

Clone LPython

git clone https://github.com/lcompilers/lpython.git
cd lpython

Create a Conda environment using the preexisting environment.yml file:

conda env create -f environment.yml
conda activate lp

Create autogenerated files (choose the command for your platform):

./build0.sh      # macOS/Linux
call build0.bat  # Windows

Compile LPython:

cmake -DCMAKE_BUILD_TYPE=Debug -DWITH_LLVM=yes -DWITH_STACKTRACE=yes -DWITH_LFORTRAN_BINARY_MODFILES=no .
cmake --build . -j16

Tests:

Run tests:

ctest
./run_tests.py

Run integration tests:

cd integration_tests
./run_tests.sh

Speed up Integration Test on Macs

Integration tests run slowly because Apple checks the hash of each executable online before running. You can turn off that feature in the Privacy tab of the Security and Privacy item of System Preferences, Developer Tools, Terminal.app, "allow the apps below to run software locally that does not meet the system's security policy."

Examples

You can run the following examples by hand in a terminal:

./src/bin/lpython examples/expr2.py
./a.out
./src/bin/lpython --show-ast examples/expr2.py
./src/bin/lpython --show-asr examples/expr2.py
./src/bin/lpython --show-cpp examples/expr2.py
./src/bin/lpython --show-llvm examples/expr2.py
./src/bin/lpython --show-c examples/expr2.py

Contributing

We welcome contributions from anyone, even if you are new to open source. It might sound daunting to contribute to a compiler at first, but please do, it is not complicated. We will help you with any technical issues and help improve your contribution so that it can be merged.

To contribute, submit a Pull Request (PR) against our repository at:

https://github.com/lcompilers/lpython

Please report any bugs you may find at our issue tracker: https://github.com/lcompilers/lpython/issues. Or, even better, fork the repository on GitHub and create a PR. We welcome all changes, big or small, and we will help you make a PR if you are new to git.

If you have any questions or need help, please ask us at Zulip () or our mailinglist.

See the CONTRIBUTING document for more information.