from __future__ import generator_stop
import itertools


def _takewhile(data, value, has_data):
    for item in data:
        if item != value:
            yield item
        else:
            break
    else:
        has_data[0] = False


def isplit(data, value):
    data = iter(data)
    has_data = [True]
    while has_data[0]:
        yield _takewhile(data, value, has_data)


def split(data, value):
    data = iter(data)
    try:
        while True:
            carry = []
            d = itertools.takewhile(value.__ne__, data)
            first = next(d)
            yield itertools.chain([first], d, carry)
            carry.extend(d)
    except StopIteration:
        pass

print('isplit')
print([list(i) for i in isplit('abc def ghi', ' ')])
s = isplit('abc def ghi', ' ')
print(list(itertools.zip_longest(*itertools.islice(s, 4))))

print('nsplit')
print([list(i) for i in split('abc def ghi', ' ')])
s = split('abc def ghi', ' ')
print(list(itertools.zip_longest(*itertools.islice(s, 4))))

isplit
[['a', 'b', 'c'], ['d', 'e', 'f'], ['g', 'h', 'i']]
[('a', 'b', 'c', None), ('d', 'e', 'f', None), (None, 'g', 'h', None), (None, 'i', None, None)]

split
[['a', 'b', 'c'], ['d', 'e', 'f'], ['g', 'h', 'i']]
[('a', 'd', 'g'), ('b', 'e', 'h'), ('c', 'f', 'i')]