Using Transients to Display Errors

if ($error) {
    set_transient("my_save_post_errors_{$post_id}_{$user_id}", $error, 45);
}
save-transient.php
if ( $error = get_transient( "my_save_post_errors_{$post_id}_{$user_id}" ) ) { ?>
    <div class="error">
        <p><?php echo $error->get_error_message(); ?></p>
    </div><?php
    delete_transient("my_save_post_errors_{$post_id}_{$user_id}");
}
display-transient-errors.php