lib_sequences.py 文件源码

def split_by(pred, seq):
    """
    Splits start of sequence, consisting of items passing predicate, from the
    rest of it. Works similar to takewhile(pred, seq), dropwhile(pred, seq),
    but works with iterator seq correctly.
    """
    a, b = _tee(seq)
    return _takewhile(pred, a), _dropwhile(pred, b)


#
# Special iteration
#