pytoolbox.itertools module

pytoolbox.itertools.chunk(objects, length, of_type=<class 'list'>)

Yield successive chunks of defined length from objects. Last chunk may be smaller.

Example usage

>>> iterable = iter(list(range(7)))
>>> list(chunk(iterable, 3))
[[0, 1, 2], [3, 4, 5], [6]]
>>> list(chunk(iterable, 3))
[]
>>> list(chunk((0, 1, (2, 3)), 1, of_type=set))
[{0}, {1}, {(2, 3)}]

pytoolbox.itertools.extract_single(objects)

Return the object from objects if there is only one object, else return objects unmodified.

Example usage

>>> extract_single({6})
6
>>> extract_single([10, 2])
[10, 2]
>>> extract_single([7])
7
>>> extract_single('!')
'!'

pytoolbox.itertools.throttle(objects, min_delay)

Consume and skips some objects to yield them at defined min_delay. First and last objects are always returned. This function is a shortcut for throttles.TimeThrottle(min_delay).throttle_iterable(objects).

Example usage

>>> import datetime, time
>>> def slow_range(*args):
...     for i in range(*args):
...         time.sleep(0.5)
...         yield i
>>> list(throttle(list(range(10)), datetime.timedelta(minutes=1)))
[0, 9]
>>> list(throttle(slow_range(3), '00:00:00.2'))
[0, 1, 2]

pytoolbox.itertools.chain(*objects, callback=<function isiterable>)

Chain the objects, handle non iterable objects gracefully.

• Set callback to a function checking if the object is iterable, defaults to isiterable().

Example usage

>>> list(chain(1, 2, '3', [4, 5], {6: 7}))
[1, 2, '3', 4, 5, 6]
>>> list(chain(1, 2, '3', callback=lambda a: True))
Traceback (most recent call last):
    ...
TypeError: 'int' object is not iterable