How to assign Multiple roles to a single user in wordpress

Question

I want to make a plugin which can assign multiple roles to a single user. Some say its not possible to assign multiple roles in wordpress then why wordpress has provided 'roles' in array form. eg when i call roles of user it returns array

$current_user=wp_get_current_user();
$user_roles = $current_user->roles;

here $user_roles will be an array return by roles.

Is there any function through which i can assign multiple role to a single user

Answer 1

All thanks to tristan, finally i assigned multiple role to a single user.This code helped me to achieve that.

 $addMemberToGroup = new WP_User($required_id);
 $addMemberToGroup->add_role( $role );

here $required_id is the id of user whom i want to assign role.