Online PHP editor | refs for F3ULn

<?php $str = 'foo'; $replacement = 'bar'; $str1 = preg_replace_callback('/^foo$/', function($match) { global $replacement; return $replacement; }, $str); $str2 = preg_replace_callback('/^foo$/', function($match, &$replacement) { return $replacement; }, $str); $str3 = preg_replace_callback('/^foo$/', function($match) use ($replacement) { return $replacement; }, $str); var_dump($str1); var_dump($str2); var_dump($str3);