3v4l.org

run code in 300+ PHP versions simultaneously
<?php $matches = []; $string = "#HelloWorld -> helloworld, #Hello_W0rld -> hello_w0rld, #Hello(World -> hello,"; preg_replace_callback("/#([a-z_0-9]+)/i", function($res) use(&$matches) { $matches[] = strtolower($res[1]); }, $string); var_dump($matches); $matches2 = []; $string2 = "@HelloWorld -> helloworld, @Hello_W0rl.d -> hello_w0rl,"; preg_replace_callback("/@([a-z_0-9]+)/i", function($res) use(&$matches2) { $matches2[] = strtolower($res[1]); }, $string2); var_dump($matches2);
Output for 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.30, 8.2.0 - 8.2.25, 8.3.0 - 8.3.13
array(3) { [0]=> string(10) "helloworld" [1]=> string(11) "hello_w0rld" [2]=> string(5) "hello" } array(2) { [0]=> string(10) "helloworld" [1]=> string(10) "hello_w0rl" }
preferences:
72.3 ms | 407 KiB | 5 Q