8. Sequence ProtocolΒΆ

Support for the sequence protocol is achieved adding functions with special names, this is done using the add-function tag.

The special function names are:

Function name Parameters Return type CPython equivalent
__len__ PyObject* self Py_ssize_t PySequence_Size
__getitem__ PyObject* self, Py_ssize_t _i PyObject* PySequence_GetItem
__setitem__ PyObject* self, Py_ssize_t _i, PyObject* _value int PySequence_SetItem
__contains__ PyObject* self, PyObject* _value int PySequence_Contains
__concat__ PyObject* self, PyObject* _other PyObject* PySequence_Concat

You just need to inform the function name to the add-function tag, without any parameter or return type information, when you do it, Shiboken will create a C function with parameters and return type defined by the table above.

The function needs to follow the same semantics of the CPython equivalent function, the only way to do it is using the inject-code tag.

A concrete example how to add sequence protocol support to a class can be found on shiboken tests, more precisely in the definition of the Str class in tests/samplebinding/typesystem_sample.xml.