Função para testar informaçoes dentro de um array

code.php

<?php
// $_POST["teste"] = "algo";
// $_POST["valor1"] = "algo";
// $_POST["valor2"] = "algo";
$array = array("teste",array("valor2","validar2"),array("valor1","validar1"),array("validar"),array("validar","isso"));
$fields = test_informations($array);
if(!empty($fields)){
    echo json_encode($fields);
}
function test_informations(array $array){
    $i = 1;
    $invalid = array();
    foreach($array as $val) {
        try{
            // If value within the array is an array, means that there is an aggregate function
            if(is_array($val)){
                if(count($val) < 2){
                    throw new Exception('Quantity of arguments passed with the '.$i.'º array is invalid');
                }
                $callback = $val[1];
                // If function dosn't exist, throw exception
                if(!function_exists($callback)){
                    throw new Exception('Function '.$callback.' not exist');
                }
                // Test if post is defined, and if value in post is not empty, finally tests the aggregate function
                if(empty($_POST[$val[0]])||!$callback($_POST[$val[0]])) {
                    $invalid[] = $val[0];
                }
            }else if(empty($_POST[$val])){
	    	$invalid[] = $val;
            }
            $i++;
        } catch (Exception $e) {
            echo $e->getMessage()."<br/>";
        }
    }
    return $invalid;
}
function validar1($field){
    return false;
}
function validar2($field){
    return true;
}

/* Return
 * Can Be logged -> Quantity of arguments passed with the 4º array is invalid
 * Can Be logged -> Function isso not exist
 * ["teste","valor2","valor1"]
*/