<?php
//FRONT CONTROLLER

$items = [
	[
		'name' => 'Andrey',
		'surname' => 'Anuchkin',
		'age' => 33,
		'email' => 'a@mail.ru'
	],

	[
		'name' => 'Kirill',
		'surname' => 'Anuchkin',
		'age' => 3,
		'email' => 'k@mail.ru'
	],

	[
		'name' => 'Ksenya',
		'surname' => 'Klimenkova',
		'age' => 28,
		'email' => 'ks@mail.ru'
	],
];

$type = "email";

$mysort = function($items) use ($type){

	foreach($items as $item):
		echo $item[$type].'<br>';
	endforeach;

};