Loop Else Clause

For both for and while loops, an else clause can be added to execute if the loop completes without a break.

An example with a for-loop is shown below.

for item in items:
    if item == target:
        break
else:
    # Executed only if loop completes without break
    print("Not found")

Loop else with return or Exceptions

The else clause only runs if the loop completes normally (no break). It does NOT run if the loop exits via return or an exception:

def find_item(items: list[int], target: int) -> int:
    for item in items:
        if item == target:
            return item      # return exits function, else does NOT run
    else:
        print("Not found")   # Only runs if no return or break
    return -1

def risky_search(items: list[int]) -> int:
    for item in items:
        if item < 0:
            raise ValueError("Negative value")  # else does NOT run
    else:
        print("All items valid")  # Only runs if loop completes normally
    return len(items)

This is the natural behavior from the lowered boolean-flag pattern—the flag is only checked if control flow reaches that point.

Implementation - 🔄 Lowered - Boolean flag pattern:

bool _loopCompleted = true;
foreach (var item in items) {
    if (item == target) { _loopCompleted = false; break; }
}
if (_loopCompleted) { Console.WriteLine("Not found"); }