If you are looping over an array, the array element is aliased to the loop variable ($_ in your case). The loop variable is just another name for the array element, it isn't a copy.

This is a feature. It's designed this way.

If you don't want to modify the original element, make a copy first. For instance: 

foreach (@array) {
    local $_ = $_;  # Change 'local' to 'my' in 5.10.
    ...
}

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In reply to Re: Changing array by changing $_? by JavaFan
in thread Changing array by changing $_? by johnvandam

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