DeferredReturn

Observed in Published Research

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Correction

Here is what's right.

A return statement returns immediately, for example:

def tick(value: int):
    if value <= 0:
        return

    value -= 1

    if value == 0:
        ring_bell()

In the above code, if value <= 0, then the return statement executes and returns from the function immediately, i.e., lines after the return statement will not be executed.

Note for advanced students: The only situation where return does not return immediately is if the return statement is located inside a try block with a corresponding finally block. In that case, the finally block will execute before returning.

Value

How can you build on this misconception?

This misconception can provide a good opportunity to discuss statement sequences as a key aspect of imperative programming.

The misconception can also be an opportunity to point out the fact that return statements located inside a try block with a corresponding finally block indeed do not return immediately. However, a full-fledged discussion of the details of exception handling may be too advanced at the time students hold this misconception.