Thomas Wouters <thomas@xs4all.net>:

The following patch adds "sq_contains" support to rangeobject, and enables
the already-written support for sq_contains in listobject and tupleobject.

The rangeobject "contains" code should be a bit more efficient than the
current default "in" implementation ;-) It might not get used much, but it's
not that much to add.

listobject.c and tupleobject.c already had code for sq_contains, and the
proper struct member was set, but the PyType structure was not extended to
include tp_flags, so the object-specific code was not getting called (Go
ahead, test it ;-). I also did this for the immutable_list_type in
listobject.c, eventhough it is probably never used. Symmetry and all that.

Objects/listobject.c

@@ -1489,6 +1489,13 @@ PyTypeObject PyList_Type = {
 	0,		/*tp_as_number*/
 	&list_as_sequence,	/*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*/
 };
 
 
@@ -1540,6 +1547,7 @@ static PySequenceMethods immutable_list_as_sequence = {
 	(intintargfunc)list_slice, /*sq_slice*/
 	(intobjargproc)immutable_list_ass, /*sq_ass_item*/
 	(intintobjargproc)immutable_list_ass, /*sq_ass_slice*/
+	(objobjproc)list_contains, /*sq_contains*/
 };
 
 static PyTypeObject immutable_list_type = {
@@ -1557,5 +1565,12 @@ static PyTypeObject immutable_list_type = {
 	0,		/*tp_as_number*/
 	&immutable_list_as_sequence,	/*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*/
 };
 

Objects/rangeobject.c

@@ -237,6 +237,23 @@ range_getattr(r, name)
 	return Py_FindMethod(range_methods, (PyObject *) r, name);
 }
 
+static int
+range_contains(r, obj)
+	rangeobject * r;
+	PyObject * obj;
+{
+	long num = PyInt_AsLong(obj);
+	
+	if (num < 0 && PyErr_Occurred())
+		return -1;
+	
+	if (num < r->start || (num - r->start) % r->step)
+		return 0;
+	if (num > (r->start + (r->len * r->step)))
+		return 0;
+	return 1;
+}
+
 static PySequenceMethods range_as_sequence = {
 	(inquiry)range_length, /*sq_length*/
 	(binaryfunc)range_concat, /*sq_concat*/
@@ -245,6 +262,7 @@ static PySequenceMethods range_as_sequence = {
 	(intintargfunc)range_slice, /*sq_slice*/
 	0,		/*sq_ass_item*/
 	0,		/*sq_ass_slice*/
+	(objobjproc)range_contains, /*sq_contains*/
 };
 
 PyTypeObject PyRange_Type = {
@@ -262,4 +280,11 @@ PyTypeObject PyRange_Type = {
 	0,			/*tp_as_number*/
 	&range_as_sequence,	/*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*/
 };

Objects/tupleobject.c

@@ -447,6 +447,12 @@ PyTypeObject PyTuple_Type = {
 	&tuple_as_sequence,	/*tp_as_sequence*/
 	0,		/*tp_as_mapping*/
 	(hashfunc)tuplehash, /*tp_hash*/
+	0,		/*tp_call*/
+	0,		/*tp_str*/
+	0,		/*tp_getattro*/
+	0,		/*tp_setattro*/
+	0,		/*tp_as_buffer*/
+	Py_TPFLAGS_DEFAULT, /*tp_flags*/
 };
 
 /* The following function breaks the notion that tuples are immutable: