That's bad advice. You should never have to use exists on an array element. It returns useless information and doesn't solve the problem you claims it solves (as explained by almut).

See modules autovivification and warnings::autoviv. (Well, the latter doesn't exist yet. Working on it.)

In reply to Re^2: Erroneous defined detection of array elements by ikegami
in thread Erroneous defined detection of array elements by Anonymous Monk

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