[Python-Dev] Code comprehensibility patch

2002年3月29日 16:24:41 -0500

----- Original Message -----
From: "Tim Peters" <tim.one@comcast.net>
> > A long time ago I wrote to Guido suggesting that I might like to
submit
> > some patches to improve the comprehensibility of the Python source.
> > ...
> > I hope it looks like an improvement to people, but please let me
know
> > if it does not.
>> I assume there was something wrong with the patch as posted, as it
looked
> like the new code used 1-space indents. It also looked like it was
made
> against an out-of-date version of typeobject.c (please use current CVS
as a
> base -- the newer type/class code is unusually volatile).

Fixed. Comments appreciated. The new code is appended for easy perusal
-Dave
-----
static PyObject *
type_getattro(PyTypeObject *type, PyObject *name)
{
 PyTypeObject *metatype = type->ob_type;
 PyObject *meta_attribute, *attribute;
 descrgetfunc meta_get;
 /* Initialize this type (we'll assume the metatype is initialized) */
 if (type->tp_dict == NULL) {
 if (PyType_Ready(type) < 0)
 return NULL;
 }
 /* No readable descriptor found yet */
 meta_get = NULL;
 /* Look for the attribute in the metatype */
 meta_attribute = _PyType_Lookup(metatype, name);
 if (meta_attribute != NULL) {
 meta_get = meta_attribute->ob_type->tp_descr_get;
 if (meta_get != NULL && PyDescr_IsData(meta_attribute)) {
 /* Data descriptors implement tp_descr_set to intercept
 * writes. Assume the attribute is not overridden in
 * type's tp_dict (and bases): call the descriptor now.
 */
 return meta_get(meta_attribute,
 (PyObject *)type, (PyObject *)metatype);
 }
 }
 /* No data descriptor found on metatype. Look in tp_dict of this
 * type and its bases */
 attribute = _PyType_Lookup(type, name);
 if (attribute != NULL) {
 /* Implement descriptor functionality, if any */
 descrgetfunc local_get = attribute->ob_type->tp_descr_get;
 if (local_get != NULL) {
 /* NULL 2nd argument indicates the descriptor was found on
 * the target object itself (or a base) */
 return local_get(attribute, (PyObject *)NULL, (PyObject *)type);
 }
 Py_INCREF(attribute);
 return attribute;
 }
 /* No attribute found in local __dict__ (or bases): use the
 * descriptor from the metatype, if any */
 if (meta_get != NULL)
 return meta_get(meta_attribute, (PyObject *)type, (PyObject
*)metatype);
 /* If an ordinary attribute was found on the metatype, return it now.
*/
 if (meta_attribute != NULL) {
 Py_INCREF(meta_attribute);
 return meta_attribute;
 }
 /* Give up */
 PyErr_Format(PyExc_AttributeError,
 "type object '%.50s' has no attribute '%.400s'",
 type->tp_name, PyString_AS_STRING(name));
 return NULL;
}