Function _decode

recipes/Python/578062_Markov/recipe-578062.py:423–435

(bytes_obj, byte_map, grid, index, block_size)

# block_size
#  - length of each edge in a grid
def _decode(bytes_obj, byte_map, grid, index, block_size):
    cache = bytes()
    index = [0] + index
    for byte in bytes_obj:
        if byte in byte_map:
            index.append(byte_map[byte])
            index = index[1:]
            decoded = eval_index(grid, block_size, index)
            index[-1] = byte_map[decoded]
            cache += bytes([decoded])
        else:
            cache += bytes([byte])
    return cache, index[1:]

# bytes_obj
#  - the bytes to decode