Course of Raku / Objects, I/O, and exceptions / Exceptions / The CATCH phaser / Exercises / Handle and continue

Solution: Handle and continue

Here is a possible solution to the task.

Code

for <ok bad ok> -> $item {
    {
        die 'boom' if $item eq 'bad';
        say "processed $item";

        CATCH {
            default {
                say "skipped ($item): {.message}";
            }
        }
    }
}

🦋 You can find the source code in the file handle-and-continue.raku.

Output

processed ok
skipped (bad): boom
processed ok

Comments

1. The CATCH phaser is inside the per-item block, so it handles a die for just that one item. Because the exception is handled there, it never escapes to stop the whole loop.

2. This is the typical use of CATCH over try: a failure in one iteration is dealt with locally, and the loop moves on to the next item. The middle item fails, but the two ok items are still processed.

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