I needed a recursive in_array function the other day and disliked all the samples I found on php.net. I wrote this one using the StandardPHPLibrary. It will recursively search through a multidimensional array and return true if the $needle is found in the $haystack.
function in_array_recursive($needle, $haystack) {
$it = new RecursiveIteratorIterator(new RecursiveArrayIterator($haystack));
foreach($it [...]
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