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15 years ago
PHP: 5.2.10-2ubuntu6.3 (default apt-get installation on actual, see Date, jaunty 9.10 Ubuntu Distro - G33kWoRDs)

Have a look at your array pointer if you copy an array - the pointer will be copied, too.

For example if you got this construct:
<?php
    $array = array('zero','one','two','three','four','five','six','seven');
    $array2 = $array;
    next($array);
    echo key($array);
    echo key($array2);

    // will output:
    // 1
    // 0
?>

But if you copy the array after you've setted the pointer, the pointer will be copied, too:
<?php
    $array = array('zero','one','two','three','four','five','six','seven');
    next($array);
    $array2 = $array;
    echo key($array);
    echo key($array2);
   
    // will output:
    // 1 
    // 1
?>

What's more is, that foreach not resetting the pointer after walk through:
<?php

    $array = array('zero','one','two','three','four','five','six','seven');
    next($array);
    $array2 = array();
    foreach($array AS $key => $value){
        echo $key;
        $array2[$key] = $value;
    }
    echo var_dump(key($array));
    echo key($array2);

    // will output for foreach:
    // 0 1 2 3 4 5 6 7
    // and for the keys
    // NULL
    // 0
?>

The php-functions seems to reset the pointer on the given position after walk through (i don't know the internal handling - there could be used a copy of the array, too):
<?php

    $array = array('zero','one','two','three','four','five','six','seven');
    next($array);
    $array2 = array_values($array);
    echo key($array);
    echo key($array2);

    // will output:
    // 1
    // 0
?>

There are a lot Methods like array_merge($array) that will neither reset the pointer of $array nor copy the pointer to $array2. Have a look on this.
I Hope this was a little helpfull.
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