pybind11/example/example-pickling.cpp
Jason Rhinelander b3f3d79f4c Rename examples files, as per #288
This renames example files from `exampleN` to `example-description`.

Specifically, the following renaming is applied:

example1 -> example-methods-and-attributes
example2 -> example-python-types
example3 -> example-operator-overloading
example4 -> example-constants-and-functions
example5 -> example-callbacks (*)
example6 -> example-sequence-and-iterators
example7 -> example-buffers
example8 -> example-custom-ref-counting
example9 -> example-modules
example10 -> example-numpy-vectorize
example11 -> example-arg-keywords-and-defaults
example12 -> example-virtual-functions
example13 -> example-keep-alive
example14 -> example-opaque-types
example15 -> example-pickling
example16 -> example-inheritance
example17 -> example-stl-binders
example18 -> example-eval
example19 -> example-custom-exceptions

* the inheritance parts of example5 are moved into example-inheritance
(previously example16), and the remainder is left as example-callbacks.

This commit also renames the internal variables ("Example1",
"Example2", "Example4", etc.) into non-numeric names ("ExampleMandA",
"ExamplePythonTypes", "ExampleWithEnum", etc.) to correspond to the
file renaming.

The order of tests is preserved, but this can easily be changed if
there is some more natural ordering by updating the list in
examples/CMakeLists.txt.
2016-07-18 16:43:18 -04:00

52 lines
1.8 KiB
C++

/*
example/example-pickling.cpp -- pickle support
Copyright (c) 2016 Wenzel Jakob <wenzel.jakob@epfl.ch>
All rights reserved. Use of this source code is governed by a
BSD-style license that can be found in the LICENSE file.
*/
#include "example.h"
class Pickleable {
public:
Pickleable(const std::string &value) : m_value(value) { }
const std::string &value() const { return m_value; }
void setExtra1(int extra1) { m_extra1 = extra1; }
void setExtra2(int extra2) { m_extra2 = extra2; }
int extra1() const { return m_extra1; }
int extra2() const { return m_extra2; }
private:
std::string m_value;
int m_extra1 = 0;
int m_extra2 = 0;
};
void init_ex_pickling(py::module &m) {
py::class_<Pickleable>(m, "Pickleable")
.def(py::init<std::string>())
.def("value", &Pickleable::value)
.def("extra1", &Pickleable::extra1)
.def("extra2", &Pickleable::extra2)
.def("setExtra1", &Pickleable::setExtra1)
.def("setExtra2", &Pickleable::setExtra2)
// For details on the methods below, refer to
// http://docs.python.org/3/library/pickle.html#pickling-class-instances
.def("__getstate__", [](const Pickleable &p) {
/* Return a tuple that fully encodes the state of the object */
return py::make_tuple(p.value(), p.extra1(), p.extra2());
})
.def("__setstate__", [](Pickleable &p, py::tuple t) {
if (t.size() != 3)
throw std::runtime_error("Invalid state!");
/* Invoke the constructor (need to use in-place version) */
new (&p) Pickleable(t[0].cast<std::string>());
/* Assign any additional state */
p.setExtra1(t[1].cast<int>());
p.setExtra2(t[2].cast<int>());
});
}