get random value from a PHP array, but make it unique

Question

I want to select a random value from a array, but keep it unique as long as possible.

For example if I\'m selecting a value 4 times from a array of 4 elements, the s

Answer 1

Easy and clean:

$colors = array('blue', 'green', 'orange');
$history = $colors;

function getColor($colors, &$history){
    if(count($history)==0)
        $history = $colors;
    return array_pop( $history );
}

echo getColor($colors, $history);