diff options
Diffstat (limited to 'Doc/c-api/typeobj.rst')
| -rw-r--r-- | Doc/c-api/typeobj.rst | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/Doc/c-api/typeobj.rst b/Doc/c-api/typeobj.rst index b3433e1..f1a8233 100644 --- a/Doc/c-api/typeobj.rst +++ b/Doc/c-api/typeobj.rst @@ -649,13 +649,19 @@ The following three fields only exist if the .. cmember:: richcmpfunc PyTypeObject.tp_richcompare - An optional pointer to the rich comparison function. + An optional pointer to the rich comparison function, whose signature is + ``PyObject *tp_richcompare(PyObject *a, PyObject *b, int op)``. - The signature is the same as for :cfunc:`PyObject_RichCompare`. The function - should return the result of the comparison (usually ``Py_True`` or - ``Py_False``). If the comparison is undefined, it must return - ``Py_NotImplemented``, if another error occurred it must return ``NULL`` and set - an exception condition. + The function should return the result of the comparison (usually ``Py_True`` + or ``Py_False``). If the comparison is undefined, it must return + ``Py_NotImplemented``, if another error occurred it must return ``NULL`` and + set an exception condition. + + .. note:: + + If you want to implement a type for which only a limited set of + comparisons makes sense (e.g. ``==`` and ``!=``, but not ``<`` and + friends), directly raise :exc:`TypeError` in the rich comparison function. This field is inherited by subtypes together with :attr:`tp_compare` and :attr:`tp_hash`: a subtype inherits all three of :attr:`tp_compare`, @@ -681,10 +687,10 @@ The following three fields only exist if the | :const:`Py_GE` | ``>=`` | +----------------+------------+ + The next field only exists if the :const:`Py_TPFLAGS_HAVE_WEAKREFS` flag bit is set. - .. cmember:: long PyTypeObject.tp_weaklistoffset If the instances of this type are weakly referenceable, this field is greater |