foreach aliases the $_ or $notUsed variables to the indexed element. That means that any changes to those variables will also change the array. Since $_ is a global (local()ized by foreach), that means that any changes to $_ without localizing it again will change the aliased element.

Solution: make sure $_ is localized before modifying it. Or use a lexical variable instead, like you do.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: Reference and $_ weirdness by Joost
in thread Reference and $_ weirdness by Marcello

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