utils

pyshortio.utils.take(n, iterable)

Return first n items of the iterable as a list.

>>> take(3, range(10))
[0, 1, 2]

If there are fewer than n items in the iterable, all of them are returned.

>>> take(10, range(3))
[0, 1, 2]

pyshortio.utils.chunked(iterable, n, strict=False)

Break iterable into lists of length n:

>>> list(chunked([1, 2, 3, 4, 5, 6], 3))
[[1, 2, 3], [4, 5, 6]]

By the default, the last yielded list will have fewer than n elements if the length of iterable is not divisible by n:

>>> list(chunked([1, 2, 3, 4, 5, 6, 7, 8], 3))
[[1, 2, 3], [4, 5, 6], [7, 8]]

To use a fill-in value instead, see the grouper() recipe.

If the length of iterable is not divisible by n and strict is True, then ValueError will be raised before the last list is yielded.

pyshortio.utils.group_by(iterable: Iterable[VT], get_key: Callable[[VT], KT]) → Dict[KT, List[VT]]

Group items by it’s key, with type hint.

Example:

>>> class Record:
...     def __init__(self, product: str, date: str, sale: int):
...         self.product = product
...         self.date = date
...         self.sale = sale

>>> records = [
...     Record("apple", "2020-01-01", 10),
...     Record("apple", "2020-01-02", 20),
...     Record("apple", "2020-01-03", 30),
...     Record("banana", "2020-01-01", 10),
...     Record("banana", "2020-01-02", 20),
...     Record("banana", "2020-01-03", 30),
... ]

>>> group_by(records, lambda x: x.product)
{
    "apple": [
        Record("apple", "2020-01-01", 10),
        Record("apple", "2020-01-02", 20),
        Record("apple", "2020-01-03", 30),
    ],
    "banana": [
        Record("banana", "2020-01-01", 10),
        Record("banana", "2020-01-02", 20),
        Record("banana", "2020-01-03", 30),
    ],
}