在python中，用户定义的class是一个PyTypeObject （ XXX_Type）对象。
#PyType_Type是一切类的基类，这是一个全局数据
PyTypeObject PyType_Type = {
PyVarObject_HEAD_INIT(&PyType_Type, )
"type", /* tp_name */
sizeof(PyHeapTypeObject), /* tp_basicsize */
sizeof(PyMemberDef), /* tp_itemsize */
(destructor)type_dealloc, /* tp_dealloc */
, /* tp_print */
, /* tp_getattr */
, /* tp_setattr */
, /* tp_compare */
(reprfunc)type_repr, /* tp_repr */
, /* tp_as_number */
, /* tp_as_sequence */
, /* tp_as_mapping */
(hashfunc)_Py_HashPointer, /* tp_hash */
(ternaryfunc)type_call, /* tp_call */
, /* tp_str */
(getattrofunc)type_getattro, /* tp_getattro */
(setattrofunc)type_setattro, /* tp_setattro */
, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
Py_TPFLAGS_BASETYPE | Py_TPFLAGS_TYPE_SUBCLASS, /* tp_flags */
type_doc, /* tp_doc */
(traverseproc)type_traverse, /* tp_traverse */
(inquiry)type_clear, /* tp_clear */
type_richcompare, /* tp_richcompare */
offsetof(PyTypeObject, tp_weaklist), /* tp_weaklistoffset */
, /* tp_iter */
, /* tp_iternext */
type_methods, /* tp_methods */
type_members, /* tp_members */
type_getsets, /* tp_getset */
, /* tp_base */
, /* tp_dict */
, /* tp_descr_get */
, /* tp_descr_set */
offsetof(PyTypeObject, tp_dict), /* tp_dictoffset */
type_init, /* tp_init */
, /* tp_alloc */
type_new, /* tp_new */
PyObject_GC_Del, /* tp_free */
(inquiry)type_is_gc, /* tp_is_gc */
};
list是一个具体的type：
PyTypeObject PyList_Type = {
PyVarObject_HEAD_INIT(&PyType_Type, )
"list",
sizeof(PyListObject),
,
(destructor)list_dealloc, /* tp_dealloc */
(printfunc)list_print, /* tp_print */
, /* tp_getattr */
, /* tp_setattr */
, /* tp_compare */
(reprfunc)list_repr, /* tp_repr */
, /* tp_as_number */
&list_as_sequence, /* tp_as_sequence */
&list_as_mapping, /* tp_as_mapping */
(hashfunc)PyObject_HashNotImplemented, /* tp_hash */
, /* tp_call */
, /* tp_str */
PyObject_GenericGetAttr, /* tp_getattro */
, /* tp_setattro */
, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
Py_TPFLAGS_BASETYPE | Py_TPFLAGS_LIST_SUBCLASS, /* tp_flags */
list_doc, /* tp_doc */
(traverseproc)list_traverse, /* tp_traverse */
(inquiry)list_clear, /* tp_clear */
list_richcompare, /* tp_richcompare */
, /* tp_weaklistoffset */
list_iter, /* tp_iter */
, /* tp_iternext */
list_methods, /* tp_methods */
, /* tp_members */
, /* tp_getset */
, /* tp_base */
, /* tp_dict */
, /* tp_descr_get */
, /* tp_descr_set */
, /* tp_dictoffset */
(initproc)list_init, /* tp_init */
PyType_GenericAlloc, /* tp_alloc */
PyType_GenericNew, /* tp_new */
PyObject_GC_Del, /* tp_free */
};
typedef struct {
PyObject_VAR_HEAD
/* Vector of pointers to list elements. list[0] is ob_item[0], etc. */
PyObject **ob_item;
/* ob_item contains space for 'allocated' elements. The number
* currently in use is ob_size.
* Invariants:
* 0 <= ob_size <= allocated
* len(list) == ob_size
* ob_item == NULL implies ob_size == allocated == 0
* list.sort() temporarily sets allocated to -1 to detect mutations.
*
* Items must normally not be NULL, except during construction when
* the list is not yet visible outside the function that builds it.
*/
Py_ssize_t allocated;
} PyListObject;
list的实例对象是PyListObject，保存了list的数据，由list对象的head可以知道他的PyList_Type，从而可以调用PyList_Type的方法。
PyTypeObject PyDict_Type = {
PyVarObject_HEAD_INIT(&PyType_Type, )
"dict",
sizeof(PyDictObject),
,
(destructor)dict_dealloc, /* tp_dealloc */
(printfunc)dict_print, /* tp_print */
, /* tp_getattr */
, /* tp_setattr */
(cmpfunc)dict_compare, /* tp_compare */
(reprfunc)dict_repr, /* tp_repr */
, /* tp_as_number */
&dict_as_sequence, /* tp_as_sequence */
&dict_as_mapping, /* tp_as_mapping */
(hashfunc)PyObject_HashNotImplemented, /* tp_hash */
, /* tp_call */
, /* tp_str */
PyObject_GenericGetAttr, /* tp_getattro */
, /* tp_setattro */
, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
Py_TPFLAGS_BASETYPE | Py_TPFLAGS_DICT_SUBCLASS, /* tp_flags */
dictionary_doc, /* tp_doc */
dict_traverse, /* tp_traverse */
dict_tp_clear, /* tp_clear */
dict_richcompare, /* tp_richcompare */
, /* tp_weaklistoffset */
(getiterfunc)dict_iter, /* tp_iter */
, /* tp_iternext */
mapp_methods, /* tp_methods */
, /* tp_members */
, /* tp_getset */
, /* tp_base */
, /* tp_dict */
, /* tp_descr_get */
, /* tp_descr_set */
, /* tp_dictoffset */
dict_init, /* tp_init */
PyType_GenericAlloc, /* tp_alloc */
dict_new, /* tp_new */
PyObject_GC_Del, /* tp_free */
};
PyTypeObject PyBaseObject_Type = {
PyVarObject_HEAD_INIT(&PyType_Type, )
"object", /* tp_name */
sizeof(PyObject), /* tp_basicsize */
, /* tp_itemsize */
object_dealloc, /* tp_dealloc */
, /* tp_print */
, /* tp_getattr */
, /* tp_setattr */
, /* tp_compare */
object_repr, /* tp_repr */
, /* tp_as_number */
, /* tp_as_sequence */
, /* tp_as_mapping */
(hashfunc)_Py_HashPointer, /* tp_hash */
, /* tp_call */
object_str, /* tp_str */
PyObject_GenericGetAttr, /* tp_getattro */
PyObject_GenericSetAttr, /* tp_setattro */
, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /* tp_flags */
PyDoc_STR("The most base type"), /* tp_doc */
, /* tp_traverse */
, /* tp_clear */
, /* tp_richcompare */
, /* tp_weaklistoffset */
, /* tp_iter */
, /* tp_iternext */
object_methods, /* tp_methods */
, /* tp_members */
object_getsets, /* tp_getset */
, /* tp_base */
, /* tp_dict */
, /* tp_descr_get */
, /* tp_descr_set */
, /* tp_dictoffset */
object_init, /* tp_init */
PyType_GenericAlloc, /* tp_alloc */
object_new, /* tp_new */
PyObject_Del, /* tp_free */
};
o=object(),object也是一种类。tp_dict有什么作用？类的__dict__是用来保存实例对象的。
>>> class t(object):
name='hai'
age=41
def __init__(self,a,b):
self.m1=a
self.m2=b
def func2():
pass >>> oo=t(5,7)
>>> oo.__dict__
{'m1': 5, 'm2': 7}
>>> t.__dict__
dict_proxy({'func2': <function func2 at 0x013AF570>, '__module__': '__main__', 'name': 'hai', 'age': 41, '__dict__': <attribute '__dict__' of 't' objects>, '__weakref__': <attribute '__weakref__' of 't' objects>, '__doc__': None, '__init__': <function __init__ at 0x013AF530>})
>>>
>>> class t(object):
name='hai'
age=41 >>> o=t()
>>> dir(o)
['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'age', 'name']
>>> o.__dict__
{}
>>> dir(t)
['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'age', 'name']
>>> type(t)
<type 'type'>
>>> o.__class__
<class '__main__.t'>
>>> t.__class__
<type 'type'>
>>>
>>> class t(object):
name='hai'
age=41
def func1():
pass
def func2():
pass >>> dir(t)
['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'age', 'func1', 'func2', 'name']
>>> o=t()
>>> dir(o)
['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'age', 'func1', 'func2', 'name']
>>>