<?php declare(strict_types = 1);

class HelloWorld
{
	public function sayHello(): void
	{
		$data = [
                    [
                        'elements' => [1, 2, 3],
                        'greet' => fn (int $value) => 'I am '.$value,
                    ],
                    [
                        'elements' => ['hello', 'world'],
                        'greet' => fn (string $value) => 'I am '.$value,
                    ],
                ];
        
                foreach ($data as $entry) {
                    foreach ($entry['elements'] as $element) {
                        $entry['greet']($element);
                    }
                }
	}
}