Various built-in types for type hinting are provided. Currently, two types exist –
GenericAlias
and
Union
. Only
GenericAlias
is exposed to C.
创建
GenericAlias
object. Equivalent to calling the Python class
types.GenericAlias
。
origin
and
args
arguments set the
GenericAlias
‘s
__origin__
and
__args__
attributes respectively.
origin
应该为
PyTypeObject
*
,和
args
可以是
PyTupleObject
*
或任何
PyObject*
。若
args
passed is not a tuple, a 1-tuple is automatically constructed and
__args__
被设为
(args,)
. Minimal checking is done for the arguments, so the function will succeed even if
origin
is not a type. The
GenericAlias
‘s
__parameters__
attribute is constructed lazily from
__args__
. On failure, an exception is raised and
NULL
被返回。
Here’s an example of how to make an extension type generic:
... static PyMethodDef my_obj_methods[] = { // Other methods. ... {"__class_getitem__", Py_GenericAlias, METH_O|METH_CLASS, "See PEP 585"} ... }
另请参阅
The data model method
__class_getitem__()
.
Added in version 3.9.
The C type of the object returned by
Py_GenericAlias()
。相当于
types.GenericAlias
in Python.
Added in version 3.9.