Modules with classes

The pet module provides the Dog and Cat classes.

Both C++ classes have a getName() and a setName() class functions.

The Dog and Cat classes are exposed in a different way to the Python code:

Dog is added to the Python module with a getter and a setter.
Cat is more pythonic and provides access to the C++ accessors as a property.

In C++, both classes are defined in the exact same way, but:

the get and set function of the Dog class are bound to functions of the same name in Python
for the Cat the name class property on the Python side is using the C++ getter and setter to read and write the name value.

py::class_<Dog>(m, "Dog")
.def(py::init<const std::string &>())
.def("setName", &Dog::setName, "Setting the dog's name")
.def("getName", &Dog::getName), "Getting the dog's name";

py::class_<Cat>(m, "Cat")
.def(py::init<const std::string &>())
.def_property("name", &Cat::getName, &Cat::setName, "The cat name");

You can compile and import the pet module, containing a Dog and a Cat classes:

$ mkdir build
$ cmake ..
$ make
$ python3
>>> import pet
>>> a = pet.Dog('Flip')
>>> print(a)
<pet.Pet object at 0x10cd98060>
>>> a.getName()
'Flip'
>>> a.setName('Flop')
>>> a.getName()
'Flop'
>>> b = pet.Cat('Fox')
>>> b.name
'Fox'
>>> b.name = 'Fix'
>>> b.name
'Fix'