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    sneskid at hotmail dot com
    16 years ago
    (v5.1.4)
    One cool thing about var_dump is it shows which variables are references (when dumping arrays), symbolized by '∫' for int/null, and by '&' for boolean/double/string/array/object. I don't know why the difference in symmmmbolism.
    After playing around I found a better way to implement detaching (twas by accident). var_dump can show what's going on.

    <?php
    function &detach($v=null){return $v;}

    $A=array('x' => 123, 'y' => 321);
    $A['x'] = &$A['x'];
    var_dump($A);
    /* x became it's own reference...
    array(2) {
      ["x"]=> ∫(123)
      ["y"]=> int(321)
    }*/

    $A['y']=&$A['x'];
    var_dump($A);
    /* now both are references
    array(2) {
      ["x"]=> ∫(123)
      ["y"]=> ∫(123)
    }*/

    $z = 'hi';
    $A['y']=&detach(&$z);
    var_dump($A);
    /* x is still a reference, y and z share
    array(2) {
      ["x"]=> ∫(123)
      ["y"]=> &string(2) "hi"
    }*/

    $A['x'] = $A['x'];
    $A['y']=&detach();
    var_dump($A,$z);
    /* x returned to normal, y is on its own, z is still "hi"
    array(2) {
      ["x"]=> int(123)
      ["y"]=> NULL
    }*/
    ?>

    For detach to work you need to use '&' in the function declaration, and every time you call it.

    Use this when you know a variable is a reference, and you want to assign a new value without effecting other vars referencing that piece of memory. You can initialize it with a new constant value, or variable, or new reference all in once step.

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