This is a free configurable implementation of the fizzbuzz problem

fizz_buzz_configurable.php

<?php
$config = array(
	'fizz' => 3,
	'buzz' => 5,
	/*
	'prim' => function($num) {
		return in_array($num, array(1, 2, 3, 5, 7, 11, 13, 17, 19, 23));
	}
	 */
);

for ($i = 1; $i < 101; $i++) {
	$output = '';
	foreach ($config as $buzzword => $divider) {
		$is_callable = is_callable($divider);
		if (($is_callable && $divider($i)) || (!$is_callable && $i % $divider === 0)) {
			$output .= $buzzword;
		}

	}

	if ($output === '') {
		$output = $i;
	}

	printf('%s ', $output);
}

echo PHP_EOL;