Course of Raku / Objects, I/O, and exceptions / Exceptions / The CATCH phaser / Exercises / Survive a loop

Solution: Survive a loop

Here is a possible solution to the task.

Code

for 1, 2, 3 -> $n {
    if $n == 2 {
        die "bad: $n";
    }
    say "ok: $n";

    CATCH {
        default {
            say "caught: " ~ .message;
        }
    }
}

🦋 You can find the source code in the file survive-a-loop.raku.

Output

ok: 1
caught: bad: 2
ok: 3

Comments

1. The CATCH phaser handles an exception thrown inside the loop body, so the die on the second iteration is caught rather than fatal.

2. Once the exception is handled, the loop simply continues with the next value, which is why ok: 3 is still printed.

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