Supported Versions: PHP 4, PHP 5, PHP 7, PHP 8
Finds whether a variable is an object
<?php is_object(mixed $value): bool
<?php     public static function becauseTheFilesystemWasNotValid($filesystem): UnableToMountFilesystem

    {

        $received = is_object($filesystem) ? get_class($filesystem) : gettype($filesystem);



        return new UnableToMountFilesystem(

            'Unable to mount filesystem, filesystem was invalid. Instance of ' . FilesystemOperator::class . ' expected, received: ' . $received