Gtk.TextIter.prototype.forward_chars

function forward_chars(count:Number):Boolean {
    // Gjs wrapper for gtk_text_iter_forward_chars()
}

Moves count characters if possible (if count would move past the start or end of the buffer, moves to the start or end of the buffer). The return value indicates whether the new position of iter is different from its original position, and dereferenceable (the last iterator in the buffer is not dereferenceable). If count is 0, the function does nothing and returns false.