43 – Read files in chunks

43 – Read files in chunks#

The built-in iter can be used to turn functions into iterables. In its not-so-well-known form, iter(f, sentinel) creates an iterable that calls the function f until the function returns the value sentinel.

For example, paired with functools.partial, you can use it to create a “chunk” reader that reads files in chunks:

from functools import partial

with open("bee-movie-script.txt", "r") as f:
    chunk_reader = iter(partial(f.read, 16), "")
    for chunk in chunk_reader:
        print(chunk)

"""
According to all
 known laws of a
viation, there i
s no way a bee s
hould be able to
...
"""