#!/usr/bin/env python3
#
# Copyright 2021 Graviti. Licensed under MIT License.
#
"""The implementation of iteration tools."""
from itertools import islice
from typing import Iterable, Iterator, Tuple, TypeVar
_T = TypeVar("_T")
[docs]def chunked(iterable: Iterable[_T], n: int) -> Iterator[Tuple[_T, ...]]:
"""Break an iterable instance into tuples of length n.
Arguments:
iterable: The input iterable instance which needs to be breaked into tuples of length n.
n: The length of each yielded tuples.
Yields:
The tuples of length n.
Examples:
>>> list(chunked(range(9), 3))
[(0, 1, 2), (3, 4, 5), (6, 7, 8)]
The last yielded tuple may have fewer than n items if the length of the input iterable
instance is not divisible by n:
>>> list(chunked(range(10), 3))
[(0, 1, 2), (3, 4, 5), (6, 7, 8), (9,)]
"""
iterator = iter(iterable)
while True:
chunk = tuple(islice(iterator, n))
if not chunk:
return
yield chunk