listextend(): New method which implements L.extend(L2).
diff --git a/Objects/listobject.c b/Objects/listobject.c
index f2c295e..df2108c 100644
--- a/Objects/listobject.c
+++ b/Objects/listobject.c
@@ -569,6 +569,77 @@
}
static PyObject *
+listextend(self, args)
+ PyListObject *self;
+ PyObject *args;
+{
+ PyObject *b = NULL, *res = NULL;
+ PyObject **items;
+ int selflen = PyList_GET_SIZE(self);
+ int blen;
+ register int i;
+
+ if (!PyArg_ParseTuple(args, "O", &b))
+ return NULL;
+
+ if (!PyList_Check(b)) {
+ PyErr_SetString(PyExc_TypeError,
+ "list.extend() argument must be a list");
+ return NULL;
+ }
+ if (PyList_GET_SIZE(b) == 0) {
+ /* short circuit when b is empty */
+ Py_INCREF(Py_None);
+ return Py_None;
+ }
+ if (self == (PyListObject*)b) {
+ /* as in list_ass_slice() we must special case the
+ * situation: a.extend(a)
+ *
+ * XXX: I think this way ought to be faster than using
+ * list_slice() the way list_ass_slice() does.
+ */
+ b = PyList_New(selflen);
+ if (!b)
+ return NULL;
+ for (i = 0; i < selflen; i++) {
+ PyObject *o = PyList_GET_ITEM(self, i);
+ Py_INCREF(o);
+ PyList_SET_ITEM(b, i, o);
+ }
+ }
+ else
+ /* we want b to have the same refcount semantics for the
+ * Py_XDECREF() in the finally clause regardless of which
+ * branch in the above conditional we took.
+ */
+ Py_INCREF(b);
+
+ blen = PyList_GET_SIZE(b);
+ /* resize a using idiom */
+ items = self->ob_item;
+ NRESIZE(items, PyObject*, selflen + blen);
+ if (items == NULL ) {
+ PyErr_NoMemory();
+ goto finally;
+ }
+ self->ob_item = items;
+
+ /* populate the end self with b's items */
+ for (i = 0; i < blen; i++) {
+ PyObject *o = PyList_GET_ITEM(b, i);
+ Py_INCREF(o);
+ PyList_SET_ITEM(self, self->ob_size++, o);
+ }
+ res = Py_None;
+ Py_INCREF(res);
+ finally:
+ Py_XDECREF(b);
+ return res;
+}
+
+
+static PyObject *
listpop(self, args)
PyListObject *self;
PyObject *args;
@@ -1309,6 +1380,8 @@
static char append_doc[] =
"L.append(object) -- append object to end";
+static char extend_doc[] =
+"L.extend(list) -- extend list by appending list elements";
static char insert_doc[] =
"L.insert(index, object) -- insert object before index";
static char pop_doc[] =
@@ -1327,6 +1400,7 @@
static PyMethodDef list_methods[] = {
{"append", (PyCFunction)listappend, 0, append_doc},
{"insert", (PyCFunction)listinsert, 0, insert_doc},
+ {"extend", (PyCFunction)listextend, 1, extend_doc},
{"pop", (PyCFunction)listpop, 1, pop_doc},
{"remove", (PyCFunction)listremove, 0, remove_doc},
{"index", (PyCFunction)listindex, 0, index_doc},