Helper functions to data structures hacking

chunk_indexes.py

def chunk_indexes(size, chunk_size):
    start = (size % chunk_size) or chunk_size
    upper_boundary = list(range(start, size + 1, chunk_size))
    lower_boundary = [0] + upper_boundary[:-1]
    return zip(lower_boundary, upper_boundary)

iterlinked.py

def iterlinked(node):
    if not node: raise StopIteration
    yield node.value
    while node.next:
        node = node.next
        yield node.value