Python Essentials

The continue and break statements

The continue statement is helpful for skipping items without writing deeply-nested if statements. The effect of executing a continue statement is to skip the rest of the loop's suite. In a for loop, this means that the next item will be taken from the source iterable. In a while loop, this must be used carefully to avoid an otherwise infinite iteration.

We might see file processing that looks like this:

for line in some_file:
    clean = line.strip()
    if len(clean) == 0:
        continue
    data, _, _ = clean.partition("#")
    data = data.rstrip()
    if len(data) == 0:
        continue
    process(data)

In this loop, we're relying on the way files act like sequences of individual lines. For each line in the file, we've stripped whitespace from the ...