Alexandrovskiy

<?php
    $leftMenu = [
        ["link"=>'Домой', 'href'=>'index.php'],
        ['link'=>'О нас', 'href'=>'about.php'],
        ['link'=>'Контакты', 'href'=>'contact.php'],
        ['link'=>'Таблица умножения', 'href'=>'table.php'],
        ['link'=>'Калькулятор', 'href'=>'calc.php'],
        ['link'=>'Демо', 'href'=>'demo',
        ['link'=>'Тест','href'=>'test.php'],
            ['link'=>'Индекс','href'=>'index.php'],
            ['link'=>'Цикл For','href'=>'for.php'],
            ['link'=>'Цикл While','href'=>'while.php'],
        ]
    ];

    function arprint($arr) {
        foreach($arr as $a) {
            if (is_array($a)) {
                print '<br>';
                arprint($a);
            } else {
                print $a . '<br>';
            }
        }
    }

    arprint($leftMenu);
?>

you don't need to do anything - it is transparently converted back to its original form when the request is parsed