diff options
Diffstat (limited to 'Modules/itertoolsmodule.c')
| -rw-r--r-- | Modules/itertoolsmodule.c | 30 |
1 files changed, 16 insertions, 14 deletions
diff --git a/Modules/itertoolsmodule.c b/Modules/itertoolsmodule.c index d45000788c..60ec11c32d 100644 --- a/Modules/itertoolsmodule.c +++ b/Modules/itertoolsmodule.c @@ -56,11 +56,13 @@ static PyTypeObject pairwise_type; /* batched object ************************************************************/ /* Note: The built-in zip() function includes a "strict" argument - that is needed because that function can silently truncate data - and there is no easy way for a user to detect that condition. - The same reasoning does not apply to batched() which never drops - data. Instead, it produces a shorter list which can be handled - as the user sees fit. + that was needed because that function would silently truncate data, + and there was no easy way for a user to detect the data loss. + The same reasoning does not apply to batched() which never drops data. + Instead, batched() produces a shorter tuple which can be handled + as the user sees fit. If requested, it would be reasonable to add + "fillvalue" support which had demonstrated value in zip_longest(). + For now, the API is kept simple and clean. */ typedef struct { @@ -74,25 +76,25 @@ typedef struct { itertools.batched.__new__ as batched_new iterable: object n: Py_ssize_t -Batch data into lists of length n. The last batch may be shorter than n. +Batch data into tuples of length n. The last batch may be shorter than n. -Loops over the input iterable and accumulates data into lists +Loops over the input iterable and accumulates data into tuples up to size n. The input is consumed lazily, just enough to -fill a list. The result is yielded as soon as a batch is full +fill a batch. The result is yielded as soon as a batch is full or when the input iterable is exhausted. >>> for batch in batched('ABCDEFG', 3): ... print(batch) ... - ['A', 'B', 'C'] - ['D', 'E', 'F'] - ['G'] + ('A', 'B', 'C') + ('D', 'E', 'F') + ('G',) [clinic start generated code]*/ static PyObject * batched_new_impl(PyTypeObject *type, PyObject *iterable, Py_ssize_t n) -/*[clinic end generated code: output=7ebc954d655371b6 input=f28fd12cb52365f0]*/ +/*[clinic end generated code: output=7ebc954d655371b6 input=ffd70726927c5129]*/ { PyObject *it; batchedobject *bo; @@ -150,12 +152,12 @@ batched_next(batchedobject *bo) if (it == NULL) { return NULL; } - result = PyList_New(n); + result = PyTuple_New(n); if (result == NULL) { return NULL; } iternextfunc iternext = *Py_TYPE(it)->tp_iternext; - PyObject **items = _PyList_ITEMS(result); + PyObject **items = _PyTuple_ITEMS(result); for (i=0 ; i < n ; i++) { item = iternext(it); if (item == NULL) { |