X-Neon / pybind_struct

Macros for exposing aggregate classes to Python using pybind11

pybind_struct

pybind_struct is a single header include that defines macros for exporting aggregate classes when using pybind11. This reduces the amount of boilerplate necessary when exposing simple structs to Python.

For example, consider the following struct:

struct example
{
    int a;
    float b;
    std::vector<double> c;
};

The macro PYBIND_STRUCT_READWRITE(example, a, b, c) is equivalent to:

py::class_<example>(m, "example")
    .def(py::init<>())
    .def(py::init<int, float, std::vector<double>>(), py::arg("a")=int{}, py::arg("b")=float{}, py::arg("c")=std::vector<double>{})
    // + Other Python magic functions, listed below
    .def_readwrite("a", &example::a)
    .def_readwrite("b", &example::b)
    .def_readwrite("c", &example::c);

There also exists PYBIND_STRUCT_READONLY which defines no constructors and read-only access to its members, and PYBIND_STRUCT_ENUM for defining enums in a similar fashion.

pybind_struct will also define magic methods on your type:

• Pickle serialization and deserialization support
• __copy__ and __deepcopy__
• __str__ if std::ostream << Type is valid
• __nonzero__ / __bool__ (depending on Python 2/3) if std::is_convertible<Type, bool> is true
• __eq__, __ne__, __lt__, __le__, __gt__ and __ge__ if Type OPERATOR Type is valid for the corresponding operator

Requirements

pybind_struct requires a C++17 compliant compiler.

Usage

To use pybind_struct, simply include the single header file:

#include "pybind_struct.hpp"