http://hg.python.org/cpython/rev/84c3be27b4c7 changeset: 71614:84c3be27b4c7 parent: 71611:a6afd26caa8a user: Benjamin Peterson <benjamin@python.org> date: Fri Jul 29 18:19:43 2011 -0500 summary: make the types of None and Ellipsis callable files: Lib/test/test_builtin.py | 7 +++++ Misc/NEWS | 3 ++ Objects/object.c | 34 ++++++++++++++++++++++++++++ Objects/sliceobject.c | 29 +++++++++++++++++++++++ 4 files changed, 73 insertions(+), 0 deletions(-) diff --git a/Lib/test/test_builtin.py b/Lib/test/test_builtin.py --- a/Lib/test/test_builtin.py +++ b/Lib/test/test_builtin.py @@ -1343,6 +1343,13 @@ self.assertRaises(ValueError, x.translate, b"1", 1) self.assertRaises(TypeError, x.translate, b"1"*256, 1) + def test_construct_singletons(self): + for const in None, Ellipsis: + tp = type(const) + self.assertIs(tp(), const) + self.assertRaises(TypeError, tp, 1, 2) + self.assertRaises(TypeError, tp, a=1, b=2) + class TestSorted(unittest.TestCase): def test_basic(self): diff --git a/Misc/NEWS b/Misc/NEWS --- a/Misc/NEWS +++ b/Misc/NEWS @@ -10,6 +10,9 @@ Core and Builtins ----------------- +- Make type(None) and type(Ellipsis) callable. They return the respective + singleton instances. + - Forbid summing bytes in sum(). - Verify the types of AST strings and identifiers provided by the user before diff --git a/Objects/object.c b/Objects/object.c --- a/Objects/object.c +++ b/Objects/object.c @@ -1277,6 +1277,16 @@ Py_FatalError("deallocating None"); } +static PyObject * +none_new(PyTypeObject *type, PyObject *args, PyObject *kwargs) +{ + if (PyTuple_GET_SIZE(args) || (kwargs && PyDict_Size(kwargs))) { + PyErr_SetString(PyExc_TypeError, "NoneType takes no arguments"); + return NULL; + } + Py_RETURN_NONE; +} + static int none_bool(PyObject *v) { @@ -1335,6 +1345,30 @@ 0, /*tp_as_sequence*/ 0, /*tp_as_mapping*/ 0, /*tp_hash */ + 0, /*tp_call */ + 0, /*tp_str */ + 0, /*tp_getattro */ + 0, /*tp_setattro */ + 0, /*tp_as_buffer */ + Py_TPFLAGS_DEFAULT, /*tp_flags */ + 0, /*tp_doc */ + 0, /*tp_traverse */ + 0, /*tp_clear */ + 0, /*tp_richcompare */ + 0, /*tp_weaklistoffset */ + 0, /*tp_iter */ + 0, /*tp_iternext */ + 0, /*tp_methods */ + 0, /*tp_members */ + 0, /*tp_getset */ + 0, /*tp_base */ + 0, /*tp_dict */ + 0, /*tp_descr_get */ + 0, /*tp_descr_set */ + 0, /*tp_dictoffset */ + 0, /*tp_init */ + 0, /*tp_alloc */ + none_new, /*tp_new */ }; PyObject _Py_NoneStruct = { diff --git a/Objects/sliceobject.c b/Objects/sliceobject.c --- a/Objects/sliceobject.c +++ b/Objects/sliceobject.c @@ -17,6 +17,17 @@ #include "structmember.h" static PyObject * +ellipsis_new(PyTypeObject *type, PyObject *args, PyObject *kwargs) +{ + if (PyTuple_GET_SIZE(args) || (kwargs && PyDict_Size(kwargs))) { + PyErr_SetString(PyExc_TypeError, "EllipsisType takes no arguments"); + return NULL; + } + Py_INCREF(Py_Ellipsis); + return Py_Ellipsis; +} + +static PyObject * ellipsis_repr(PyObject *op) { return PyUnicode_FromString("Ellipsis"); @@ -43,6 +54,24 @@ 0, /* tp_setattro */ 0, /* tp_as_buffer */ Py_TPFLAGS_DEFAULT, /* tp_flags */ + 0, /* tp_doc */ + 0, /* tp_traverse */ + 0, /* tp_clear */ + 0, /* tp_richcompare */ + 0, /* tp_weaklistoffset */ + 0, /* tp_iter */ + 0, /* tp_iternext */ + 0, /* tp_methods */ + 0, /* tp_members */ + 0, /* tp_getset */ + 0, /* tp_base */ + 0, /* tp_dict */ + 0, /* tp_descr_get */ + 0, /* tp_descr_set */ + 0, /* tp_dictoffset */ + 0, /* tp_init */ + 0, /* tp_alloc */ + ellipsis_new, /* tp_new */ }; PyObject _Py_EllipsisObject = { -- Repository URL: http://hg.python.org/cpython