- var_dump: documentation ( source)
- function_exists: documentation ( source)
- extension_loaded: documentation ( source)
<?php
var_dump(defined('INTL_IDNA_VARIANT_2003'));
var_dump(defined('INTL_IDNA_VARIANT_UTS46'));
var_dump(function_exists('idn_to_ascii'));
var_dump(extension_loaded('intl'));