Example of Pythran Usage Within a Full Project

This notebook covers the creation of a simple, distutils-powered, project that ships a pythran kernel.

But first some cleanup

[1]:
!rm -rf hello setup.py && mkdir hello

Project layout

The Pythran file is really dumb. The expected layout is:

setup.py
hello/
  +---- __init__.py
  +---- hello.py
[2]:
%%file hello/hello.py

#pythran export hello()

def hello():
    """
    Wave hello.
    """
    print("Hello from Pythran o/")
Writing hello/hello.py

And so is the __init__.py file.

[3]:
%%file hello/__init__.py
"""
Hello package, featuring a Pythran kernel.
"""
from hello import hello
Writing hello/__init__.py

The setup.py file conatins the classical metadata, plus a special header. this header basically states if pythran is available, use it, otherwise fallback to the python file.

[4]:
%%file setup.py
from distutils.core import setup

try:
    from pythran.dist import PythranExtension, PythranBuildExt
    setup_args = {
        'cmdclass': {"build_ext": PythranBuildExt},
        'ext_modules': [PythranExtension('hello.hello', sources = ['hello/hello.py'])],
    }
except ImportError:
    print("Not building Pythran extension")
    setup_args = {}

setup(name = 'hello',
      version = '1.0',
      description = 'Yet another demo package',
      packages = ['hello'],
      **setup_args)
Writing setup.py

Running setup.py

With the described configuration, the normal python setup.py targets should « just work ».

If pythran is in the path, it is used to generate the alternative c++ extension when building a source release. Note the hello.cpp!

[5]:
%%sh
rm -rf build dist
python setup.py sdist 2>/dev/null 1>/dev/null
tar tf dist/hello-1.0.tar.gz
hello-1.0/
hello-1.0/hello/
hello-1.0/hello/hello.cpp
hello-1.0/hello/hello.py
hello-1.0/hello/__init__.py
hello-1.0/setup.py
hello-1.0/PKG-INFO

But if pythran is no longer in the PYTHONPATH, the installation does not fail: the regular Python source can still be used.

[6]:
%%sh
rm -rf build dist
PYTHONPATH= python setup.py sdist 2>/dev/null 1>/dev/null
tar tf dist/hello-1.0.tar.gz
hello-1.0/
hello-1.0/hello/
hello-1.0/hello/hello.py
hello-1.0/hello/__init__.py
hello-1.0/setup.py
hello-1.0/PKG-INFO

In case of binary distribution, the native module is generated alongside the original source.

[7]:
%%sh
rm -rf build dist
python setup.py bdist 2>/dev/null 1>/dev/null
tar tf dist/hello-1.0.linux-x86_64.tar.gz | grep 'hello/.*' -o
hello/
hello/__init__.pyc
hello/hello.pyc
hello/hello.so
hello/hello.py
hello/__init__.py

And if pythran is not in the PYTHONPATH, this still work \o/

[8]:
%%sh
rm -rf build dist
PYTHONPATH= python setup.py bdist 2>/dev/null 1>/dev/null
tar tf dist/hello-1.0.linux-x86_64.tar.gz | grep 'hello/.*' -o
hello/
hello/__init__.pyc
hello/hello.pyc
hello/hello.py
hello/__init__.py