In a word, aliasing. Foreach loop variables are aliased to the elements they are iterating over. Modifying the loop variable modifies the original element.

If you hard-code your list into the loop, instead of using an array, you'll get an error when it tries to modify it.

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In reply to Re: Variable scoping, foreach loop, alias by Roy Johnson
in thread Variable scoping, foreach loop, alias by Vaati

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