>>> import cppyy
>>> cppyy.cppdef("""
... class MyClass {
... public:
...     MyClass(int i) : m_data(i) {}
...     virtual ~MyClass() {}
...     virtual int add_int(int i) { return m_data + i; }
...     int m_data;
... };""")
True
>>> from cppyy.gbl import MyClass
>>> m = MyClass(42)
>>> cppyy.cppdef("""
... void say_hello(MyClass* m) {
...     std::cout << "Hello, the number is: " << m->m_data << std::endl;
... }""")
True
>>> MyClass.say_hello = cppyy.gbl.say_hello
>>> m.say_hello()
Hello, the number is: 42
>>> m.m_data = 13
>>> m.say_hello()
Hello, the number is: 13
>>> class PyMyClass(MyClass):
...     def add_int(self, i):  # python side override (CPython only)
...         return self.m_data + 2*i
...
>>> cppyy.cppdef("int callback(MyClass* m, int i) { return m->add_int(i); }")
True
>>> cppyy.gbl.callback(m, 2)             # calls C++ add_int
15
>>> cppyy.gbl.callback(PyMyClass(1), 2)  # calls Python-side override
5
>>>

>>> import cppyy
>>> cppyy.include('boost/any.hpp')       # assumes you have boost installed
>>> from cppyy.gbl import std, boost
>>> val = boost.any()                    # the capsule
>>> val.__assign__(std.vector[int]())    # assign it a std::vector

>>> val.type() == cppyy.typeid(std.vector[int])    # verify type
True
>>> extract = boost.any_cast[int](std.move(val))   # wrong cast
Traceback (most recent call last):
  File "", line 1, in 
cppyy.gbl.boost.bad_any_cast: Could not instantiate any_cast:
  int boost::any_cast(boost::any&& operand) =>
    wrapexcept: boost::bad_any_cast: failed conversion using boost::any_cast
>>> extract = boost.any_cast[std.vector[int]](val) # correct cast
>>> type(extract) is std.vector[int]
True
>>> extract += xrange(100)
>>> len(extract)
100
>>> val.__assign__(std.move(extract))    # move forced

>>> len(extract)                         # now empty (or invalid)
0
>>> extract = boost.any_cast[std.vector[int]](val)
>>> list(extract)
[0, 1, 2, 3, 4, 5, 6, ..., 97, 98, 99]
>>>