Generalize PySequence_Count() (operator.countOf) to work with iterators.
diff --git a/Objects/abstract.c b/Objects/abstract.c
index a0a40e8..21c1ef1 100644
--- a/Objects/abstract.c
+++ b/Objects/abstract.c
@@ -1333,34 +1333,52 @@
return v;
}
+/* Return # of times o appears in s. */
int
PySequence_Count(PyObject *s, PyObject *o)
{
- int l, i, n, cmp, err;
- PyObject *item;
+ int n; /* running count of o hits */
+ PyObject *it; /* iter(s) */
if (s == NULL || o == NULL) {
null_error();
return -1;
}
-
- l = PySequence_Size(s);
- if (l < 0)
+
+ it = PyObject_GetIter(s);
+ if (it == NULL) {
+ type_error(".count() requires iterable argument");
return -1;
+ }
n = 0;
- for (i = 0; i < l; i++) {
- item = PySequence_GetItem(s, i);
- if (item == NULL)
- return -1;
- err = PyObject_Cmp(item, o, &cmp);
+ for (;;) {
+ int cmp;
+ PyObject *item = PyIter_Next(it);
+ if (item == NULL) {
+ if (PyErr_Occurred())
+ goto Fail;
+ break;
+ }
+ cmp = PyObject_RichCompareBool(o, item, Py_EQ);
Py_DECREF(item);
- if (err < 0)
- return err;
- if (cmp == 0)
+ if (cmp < 0)
+ goto Fail;
+ if (cmp > 0) {
+ if (n == INT_MAX) {
+ PyErr_SetString(PyExc_OverflowError,
+ "count exceeds C int size");
+ goto Fail;
+ }
n++;
+ }
}
+ Py_DECREF(it);
return n;
+
+Fail:
+ Py_DECREF(it);
+ return -1;
}
/* Return -1 if error; 1 if v in w; 0 if v not in w. */