No, the loop won't exit even if [ undef ] or [ 0 ] is returned.

It isn't supposed to. The loop exists when you return undef to stop the loop. Read carefully :) Dumb, non-question: How to return 'nothing'.

In reply to Re^7: Dumb, non-question: How to return 'nothing'. by Anonymous Monk
in thread Dumb, non-question: How to return 'nothing'. by BrowserUk

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