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copied!<p>After the first foreach loop, <code>$item</code> is still a reference to some value which is also being used by <code>$arr[2]</code>. So each foreach call in the second loop, which does not call by reference, replaces that value, and thus <code>$arr[2]</code>, with the new value.</p> <p>So loop 1, the value and <code>$arr[2]</code> become <code>$arr[0]</code>, which is 'foo'.<br> Loop 2, the value and <code>$arr[2]</code> become <code>$arr[1]</code>, which is 'bar'.<br> Loop 3, the value and <code>$arr[2]</code> become <code>$arr[2]</code>, which is 'bar' (because of loop 2).</p> <p>The value 'baz' is actually lost at the first call of the second foreach loop.</p> <h2>Debugging the Output</h2> <p>For each iteration of the loop, we'll echo the value of <code>$item</code> as well as recursively print the array <code>$arr</code>.</p> <p>When the first loop is run through, we see this output:</p> <pre><code>foo Array ( [0] => foo [1] => bar [2] => baz ) bar Array ( [0] => foo [1] => bar [2] => baz ) baz Array ( [0] => foo [1] => bar [2] => baz ) </code></pre> <p>At the end of the loop, <code>$item</code> is still pointing to the same place as <code>$arr[2]</code>.</p> <p>When the second loop is run through, we see this output:</p> <pre><code>foo Array ( [0] => foo [1] => bar [2] => foo ) bar Array ( [0] => foo [1] => bar [2] => bar ) bar Array ( [0] => foo [1] => bar [2] => bar ) </code></pre> <p>You'll notice how each time array put a new value into <code>$item</code>, it also updated <code>$arr[3]</code> with that same value, since they are both still pointing to the same location. When the loop gets to the third value of the array, it will contain the value <code>bar</code> because it was just set by the previous iteration of that loop.</p> <h2>Is it a bug?</h2> <p>No. This is the behavior of a referenced item, and not a bug. It would be similar to running something like:</p> <pre><code>for ($i = 0; $i < count($arr); $i++) { $item = $arr[$i]; } </code></pre> <p>A foreach loop isn't special in nature in which it can ignore referenced items. It's simply setting that variable to the new value each time like you would outside of a loop.</p>

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