Supported Versions: PHP 4, PHP 5, PHP 7, PHP 8
Checks whether a constant with the given name exists
<?php defined(string $constant_name): bool
<?php                 ('\\' !== DIRECTORY_SEPARATOR || false === strpos($glob, '[^'))

            ) {


                $results = glob($glob, defined('GLOB_BRACE') ? GLOB_BRACE : 0);




                if (empty($results)) {
<?php     public function testGlobEscape()

    {

        if (defined('PHP_WINDOWS_VERSION_MAJOR')) {

            $this->markTestSkipped('A "*" in filenames is not supported on Windows.');



            return;
<?php     public function testIterateEscaped()

    {

        if (defined('PHP_WINDOWS_VERSION_MAJOR')) {

            $this->markTestSkipped('A "*" in filenames is not supported on Windows.');



            return;
<?php     public function testIterateSpecialChars()

    {

        if (defined('PHP_WINDOWS_VERSION_MAJOR')) {

            $this->markTestSkipped('A "*" in filenames is not supported on Windows.');



            return;