In your third one-liner example, $a plausibly could be undefined. I think that the OPs problem is that an array-type variable, @a, is being assigned an array reference, $href. Not sure why Perl is complaining about an "undefined variable" in that case, however.

In reply to Re^2: Array dereference in foreach() by Anonymous Monk
in thread Array dereference in foreach() by pme

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