Method peek

net/asio_error_handler.cpp:54–58

	}
	
	asio_error_handler::error peek() {
		if(unhandled == 0) return {};
		const auto prev_idx = (idx == 0 ? size - 1 : idx - 1);
		return errors[prev_idx];
	}
	
	bool empty() const {
		return (unhandled == 0);