/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsISupports.idl"

/**
 * Type for IMAP UIDs.
 * IMAP defines UIDs as non-zero unsigned 32bit integers.
 * Also used for sequence numbers, on particularly backward servers.
 *
 * General guidelines:
 * - ImapUid can hold zero to indicate an invalid/missing UID.
 * - You should _never_ encounter a `ImapUid` of `nsMsgKey_None`.
 * - Sets/arrays of ImapUIds should _never_ include zeros (although you can have an empty set)
 *
 * Ideally this typedef would prevent accidental casting to/from uint32_t and
 * (especially) nsMsgKey, but there doesn't seem to be a simple way to enforce
 * that with XPCOM.
 */
typedef unsigned long ImapUid;