<?php

$foo = function (int $val1, float $val2) : string {
    var_dump($val1, $val2);
    return $val1 + $val2;
};

var_dump($foo('4', 6));


int(4)
float(6)
string(2) "10"

• Make languages readable with Transliterator
• Little game with MultipleIterator
• Introduced in PHP 7: IntlChar class containing static methods for characters

PHP 7.3, Zend 3.0, Symfony 4.3, Laravel 5.8, PHPUnit 8.0, Doctrine 2.10