function_exists

Supported Versions: PHP 4, PHP 5, PHP 7, PHP 8
Return true if the given function has been defined
function_exists(string $function): bool
            return $s;

        }



        if (!
\function_exists('iconv')) {

            throw new 
\RuntimeException('Unable to convert a non-UTF-8 string to UTF-8: required function iconv() does not exist. You should install ext-iconv or symfony/polyfill-iconv.');

        }
        }



        if (
\DIRECTORY_SEPARATOR === '\\') {

            return (
\function_exists('sapi_windows_vt100_support')

                && @
sapi_windows_vt100_support($stream))

                || 
false !== getenv('ANSICON')

                || 
'ON' === getenv('ConEmuANSI')
use Symfony\Component\VarDumper\VarDumper;



if (!
function_exists('dump')) {
    }

}



if (!
function_exists('dd')) {