[Python-checkins] CVS: python/dist/src/Objects typeobject.c,2.134,2.135

[Guido van Rossum]

Update of /cvsroot/python/python/dist/src/Objects
In directory usw-pr-cvs1:/tmp/cvs-serv7166

Modified Files:
	typeobject.c 
Log Message:
Clarifying code rearrangement and comments by David Abrahams.  I've
got to admit that I haven't reviewed this carefully, but it looks okay
from 30,000 views, and doesn't break anything.  (SF patch 536407.)


Index: typeobject.c
===================================================================
RCS file: /cvsroot/python/python/dist/src/Objects/typeobject.c,v
retrieving revision 2.134
retrieving revision 2.135
diff -C2 -d -r2.134 -r2.135
*** typeobject.c	3 Apr 2002 02:13:37 -0000	2.134
--- typeobject.c	4 Apr 2002 17:50:54 -0000	2.135
***************
*** 1237,1242 ****
  {
  	PyTypeObject *metatype = type->ob_type;
! 	PyObject *descr, *res;
! 	descrgetfunc f;
  
  	/* Initialize this type (we'll assume the metatype is initialized) */
--- 1237,1242 ----
  {
  	PyTypeObject *metatype = type->ob_type;
! 	PyObject *meta_attribute, *attribute;
! 	descrgetfunc meta_get;
  
  	/* Initialize this type (we'll assume the metatype is initialized) */
***************
*** 1246,1283 ****
  	}
  
! 	/* Get a descriptor from the metatype */
! 	descr = _PyType_Lookup(metatype, name);
! 	f = NULL;
! 	if (descr != NULL) {
! 		f = descr->ob_type->tp_descr_get;
! 		if (f != NULL && PyDescr_IsData(descr))
! 			return f(descr,
! 				 (PyObject *)type, (PyObject *)metatype);
! 	}
  
! 	/* Look in tp_dict of this type and its bases */
! 	res = _PyType_Lookup(type, name);
! 	if (res != NULL) {
! 		f = res->ob_type->tp_descr_get;
! 		if (f != NULL)
! 			return f(res, (PyObject *)NULL, (PyObject *)type);
! 		Py_INCREF(res);
! 		return res;
  	}
  
! 	/* Use the descriptor from the metatype */
! 	if (f != NULL) {
! 		res = f(descr, (PyObject *)type, (PyObject *)metatype);
! 		return res;
  	}
! 	if (descr != NULL) {
! 		Py_INCREF(descr);
! 		return descr;
  	}
  
  	/* Give up */
  	PyErr_Format(PyExc_AttributeError,
! 		     "type object '%.50s' has no attribute '%.400s'",
! 		     type->tp_name, PyString_AS_STRING(name));
  	return NULL;
  }
--- 1246,1301 ----
  	}
  
! 	/* 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;
  }