后浪云Python教程:类型注解对象
类型注解对象
提供几种用于类型提示的内置类型。 目前存在两种类型 — GenericAlias 和 Union。 只有 GenericAlias
会向 C 开放。
PyObject *Py_GenericAlias(PyObject *origin, PyObject *args)
Part of the Stable ABI since version 3.9.
Create a GenericAlias object. Equivalent to calling the python class types.GenericAlias. The origin and args arguments set the GenericAlias
‘s __origin__
and __args__
attributes respectively. origin should be a PyTypeObject*, and args can be a PyTupleObject* or any PyObject*
. If args passed is not a tuple, a 1-tuple is automatically constructed and __args__
is set to (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
is returned.
下面是一个如何创建一个扩展类型泛型的例子:
...
static PyMethodDef my_obj_methods[] = {
// Other methods.
...
{"__class_getitem__", Py_GenericAlias, METH_O|METH_CLASS, "See PEP 585"}
...
}
参见
数据模型的方法 __class_getitem__()
。
3.9 新版功能.
PyTypeObject Py_GenericAliasType
Part of the Stable ABI since version 3.9.
由 Py_GenericAlias() 所返回的对象的 C 类型。等价于 Python 中的 types.GenericAlias 。
3.9 新版功能.