Define $listify() $li helper function

[younishd]

$listify = $li = function (
    array $items,
    string $item_format = '<li>%s</li>',
    string $list_format = '<ul>%s</ul>'
) {
    return \sprintf($list_format, \implode("\n", \array_map(function ($a) use ($item_format) {
        return \sprintf($item_format, \htmlspecialchars($a));
    }, $items)));
};

echo $li(["apple", "orange", "mango"]);
echo $listify(["apple", "orange", "mango"]);
echo $listify(["apple", "orange", "mango"], '<li class="fruit">%s<li>');
echo $listify(["apple", "orange", "mango"], '<li class="fruit">%s<li>', '<ol>%s</ol>');

<ul><li>apple</li>
<li>orange</li>
<li>mango</li></ul>

<ul><li>apple</li>
<li>orange</li>
<li>mango</li></ul>

<ul><li class="fruit">apple<li>
<li class="fruit">orange<li>
<li class="fruit">mango<li></ul>

<ol><li class="fruit">apple<li>
<li class="fruit">orange<li>
<li class="fruit">mango<li></ol>