Rolling or sliding window iterator?

There’s one in an old version of the Python docs with itertools examples:

from itertools import islice

def window(seq, n=2):
    "Returns a sliding window (of width n) over data from the iterable"
    "   s -> (s0,s1,...s[n-1]), (s1,s2,...,sn), ...                   "
    it = iter(seq)
    result = tuple(islice(it, n))
    if len(result) == n:
        yield result
    for elem in it:
        result = result[1:] + (elem,)
        yield result

The one from the docs is a little more succinct and uses itertools to greater effect I imagine.

---

If your iterator is a simple list/tuple a simple way to slide through it with a specified window size would be:

seq = [0, 1, 2, 3, 4, 5]
window_size = 3

for i in range(len(seq) - window_size + 1):
    print(seq[i: i + window_size])

Output:

[0, 1, 2]
[1, 2, 3]
[2, 3, 4]
[3, 4, 5]