mirror of
https://github.com/pybind/pybind11.git
synced 2024-11-25 14:45:12 +00:00
129 lines
5.7 KiB
Markdown
129 lines
5.7 KiB
Markdown
|
|
|
|
# pybind11 — Seamless operability between C++11 and Python
|
|
|
|
[](http://pybind11.readthedocs.org/en/master/?badge=master)
|
|
[](http://pybind11.readthedocs.org/en/stable/?badge=stable)
|
|
[](https://gitter.im/pybind/Lobby)
|
|
[](https://travis-ci.org/pybind/pybind11)
|
|
[](https://ci.appveyor.com/project/wjakob/pybind11)
|
|
|
|
**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.x, or PyPy2.7 >= 5.7) 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
|
|
[http://pybind11.readthedocs.org/en/master](http://pybind11.readthedocs.org/en/master).
|
|
A PDF version of the manual is available
|
|
[here](https://media.readthedocs.org/pdf/pybind11/master/pybind11.pdf).
|
|
|
|
## 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
|
|
- Iterators and ranges
|
|
- 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.x, and PyPy (PyPy2.7 >= 5.7) 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 17 or newer (16 with pybind11 v2.0 and 15 with pybind11 v2.0 and a [workaround](https://github.com/pybind/pybind11/issues/276))
|
|
5. Cygwin/GCC (tested on 2.5.1)
|
|
|
|
## 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,
|
|
Sylvain Corlay,
|
|
Trent Houliston,
|
|
Axel Huebl,
|
|
@hulucc,
|
|
Sergey Lyskov
|
|
Johan Mabille,
|
|
Tomasz Miąsko,
|
|
Dean Moldovan,
|
|
Ben Pritchard,
|
|
Jason Rhinelander,
|
|
Boris Schäling,
|
|
Pim Schellart,
|
|
Ivan Smirnov, and
|
|
Patrick Stewart.
|
|
|
|
### License
|
|
|
|
pybind11 is provided under a BSD-style license that can be found in the
|
|
``LICENSE`` file. By using, distributing, or contributing to this project,
|
|
you agree to the terms and conditions of this license.
|