mirror of
https://github.com/pybind/pybind11.git
synced 2024-11-11 08:03:55 +00:00
176 lines
7.1 KiB
ReStructuredText
176 lines
7.1 KiB
ReStructuredText
.. figure:: https://github.com/pybind/pybind11/raw/master/docs/pybind11-logo.png
|
||
:alt: pybind11 logo
|
||
|
||
**pybind11 — Seamless operability between C++11 and Python**
|
||
|
||
|Latest Documentation Status| |Stable Documentation Status| |Gitter chat| |CI| |Build status|
|
||
|
||
.. warning::
|
||
|
||
Combining older versions of pybind11 (< 2.6.0) with the brand-new Python
|
||
3.9.0 will trigger undefined behavior that typically manifests as crashes
|
||
during interpreter shutdown (but could also destroy your data. **You have been
|
||
warned.**)
|
||
|
||
We recommend that you wait for Python 3.9.1 slated for release in December,
|
||
which will include a `fix <https://github.com/python/cpython/pull/22670>`_
|
||
that resolves this problem. In the meantime, please update to the latest
|
||
version of pybind11 (2.6.0 or newer), which includes a temporary workaround
|
||
specifically when Python 3.9.0 is detected at runtime.
|
||
|
||
**pybind11** is a lightweight header-only library that exposes C++ types
|
||
in Python and vice versa, mainly to create Python bindings of existing
|
||
C++ code. Its goals and syntax are similar to the excellent
|
||
`Boost.Python <http://www.boost.org/doc/libs/1_58_0/libs/python/doc/>`_
|
||
library by David Abrahams: to minimize boilerplate code in traditional
|
||
extension modules by inferring type information using compile-time
|
||
introspection.
|
||
|
||
The main issue with Boost.Python—and the reason for creating such a
|
||
similar project—is Boost. Boost is an enormously large and complex suite
|
||
of utility libraries that works with almost every C++ compiler in
|
||
existence. This compatibility has its cost: arcane template tricks and
|
||
workarounds are necessary to support the oldest and buggiest of compiler
|
||
specimens. Now that C++11-compatible compilers are widely available,
|
||
this heavy machinery has become an excessively large and unnecessary
|
||
dependency.
|
||
|
||
Think of this library as a tiny self-contained version of Boost.Python
|
||
with everything stripped away that isn’t relevant for binding
|
||
generation. Without comments, the core header files only require ~4K
|
||
lines of code and depend on Python (2.7 or 3.5+, or PyPy) and the C++
|
||
standard library. This compact implementation was possible thanks to
|
||
some of the new C++11 language features (specifically: tuples, lambda
|
||
functions and variadic templates). Since its creation, this library has
|
||
grown beyond Boost.Python in many ways, leading to dramatically simpler
|
||
binding code in many common situations.
|
||
|
||
Tutorial and reference documentation is provided at
|
||
`pybind11.readthedocs.io <https://pybind11.readthedocs.io/en/latest>`_.
|
||
A PDF version of the manual is available
|
||
`here <https://pybind11.readthedocs.io/_/downloads/en/latest/pdf/>`_.
|
||
And the source code is always available at
|
||
`github.com/pybind/pybind11 <https://github.com/pybind/pybind11>`_.
|
||
|
||
|
||
Core features
|
||
-------------
|
||
|
||
|
||
pybind11 can map the following core C++ features to Python:
|
||
|
||
- Functions accepting and returning custom data structures per value,
|
||
reference, or pointer
|
||
- Instance methods and static methods
|
||
- Overloaded functions
|
||
- Instance attributes and static attributes
|
||
- Arbitrary exception types
|
||
- Enumerations
|
||
- Callbacks
|
||
- Iterators and ranges
|
||
- Custom operators
|
||
- Single and multiple inheritance
|
||
- STL data structures
|
||
- Smart pointers with reference counting like ``std::shared_ptr``
|
||
- Internal references with correct reference counting
|
||
- C++ classes with virtual (and pure virtual) methods can be extended
|
||
in Python
|
||
|
||
Goodies
|
||
-------
|
||
|
||
In addition to the core functionality, pybind11 provides some extra
|
||
goodies:
|
||
|
||
- Python 2.7, 3.5+, and PyPy/PyPy3 7.3 are supported with an
|
||
implementation-agnostic interface.
|
||
|
||
- It is possible to bind C++11 lambda functions with captured
|
||
variables. The lambda capture data is stored inside the resulting
|
||
Python function object.
|
||
|
||
- pybind11 uses C++11 move constructors and move assignment operators
|
||
whenever possible to efficiently transfer custom data types.
|
||
|
||
- It’s easy to expose the internal storage of custom data types through
|
||
Pythons’ buffer protocols. This is handy e.g. for fast conversion
|
||
between C++ matrix classes like Eigen and NumPy without expensive
|
||
copy operations.
|
||
|
||
- pybind11 can automatically vectorize functions so that they are
|
||
transparently applied to all entries of one or more NumPy array
|
||
arguments.
|
||
|
||
- Python’s slice-based access and assignment operations can be
|
||
supported with just a few lines of code.
|
||
|
||
- Everything is contained in just a few header files; there is no need
|
||
to link against any additional libraries.
|
||
|
||
- Binaries are generally smaller by a factor of at least 2 compared to
|
||
equivalent bindings generated by Boost.Python. A recent pybind11
|
||
conversion of PyRosetta, an enormous Boost.Python binding project,
|
||
`reported <http://graylab.jhu.edu/RosettaCon2016/PyRosetta-4.pdf>`_
|
||
a binary size reduction of **5.4x** and compile time reduction by
|
||
**5.8x**.
|
||
|
||
- Function signatures are precomputed at compile time (using
|
||
``constexpr``), leading to smaller binaries.
|
||
|
||
- With little extra effort, C++ types can be pickled and unpickled
|
||
similar to regular Python objects.
|
||
|
||
Supported compilers
|
||
-------------------
|
||
|
||
1. Clang/LLVM 3.3 or newer (for Apple Xcode’s clang, this is 5.0.0 or
|
||
newer)
|
||
2. GCC 4.8 or newer
|
||
3. Microsoft Visual Studio 2015 Update 3 or newer
|
||
4. Intel C++ compiler 18 or newer
|
||
(`possible issue <https://github.com/pybind/pybind11/pull/2573>`_ on 20.2)
|
||
5. Cygwin/GCC (tested on 2.5.1)
|
||
6. NVCC (CUDA 11.0 tested)
|
||
7. NVIDIA PGI (20.7 and 20.9 tested)
|
||
|
||
About
|
||
-----
|
||
|
||
This project was created by `Wenzel
|
||
Jakob <http://rgl.epfl.ch/people/wjakob>`_. Significant features and/or
|
||
improvements to the code were contributed by Jonas Adler, Lori A. Burns,
|
||
Sylvain Corlay, Eric Cousineau, Ralf Grosse-Kunstleve, Trent Houliston, Axel
|
||
Huebl, @hulucc, Yannick Jadoul, Sergey Lyskov Johan Mabille, Tomasz Miąsko,
|
||
Dean Moldovan, Ben Pritchard, Jason Rhinelander, Boris Schäling, Pim
|
||
Schellart, Henry Schreiner, Ivan Smirnov, Boris Staletic, and Patrick Stewart.
|
||
|
||
We thank Google for a generous financial contribution to the continuous
|
||
integration infrastructure used by this project.
|
||
|
||
|
||
Contributing
|
||
~~~~~~~~~~~~
|
||
|
||
See the `contributing
|
||
guide <https://github.com/pybind/pybind11/blob/master/.github/CONTRIBUTING.md>`_
|
||
for information on building and contributing to pybind11.
|
||
|
||
License
|
||
~~~~~~~
|
||
|
||
pybind11 is provided under a BSD-style license that can be found in the
|
||
`LICENSE <https://github.com/pybind/pybind11/blob/master/LICENSE>`_
|
||
file. By using, distributing, or contributing to this project, you agree
|
||
to the terms and conditions of this license.
|
||
|
||
.. |Latest Documentation Status| image:: https://readthedocs.org/projects/pybind11/badge?version=latest
|
||
:target: http://pybind11.readthedocs.org/en/latest
|
||
.. |Stable Documentation Status| image:: https://img.shields.io/badge/docs-stable-blue
|
||
:target: http://pybind11.readthedocs.org/en/stable
|
||
.. |Gitter chat| image:: https://img.shields.io/gitter/room/gitterHQ/gitter.svg
|
||
:target: https://gitter.im/pybind/Lobby
|
||
.. |CI| image:: https://github.com/pybind/pybind11/workflows/CI/badge.svg
|
||
:target: https://github.com/pybind/pybind11/actions
|
||
.. |Build status| image:: https://ci.appveyor.com/api/projects/status/riaj54pn4h08xy40?svg=true
|
||
:target: https://ci.appveyor.com/project/wjakob/pybind11
|