proc `[]`(ps: var PreambleStore; msgId: MessageId): PreambleInfo {.
    ...raises: [KeyError], tags: [], forbids: [].}

proc `[]=`(ps: var PreambleStore; msgId: MessageId; entry: PreambleInfo) {.
    ...raises: [], tags: [], forbids: [].}

proc addPossiblePeerToQuery(ps: var PreambleStore; msgId: MessageId;
                            peer: PubSubPeer) {....raises: [], tags: [],
    forbids: [].}

proc del(ps: var PreambleStore; msgId: MessageId) {....raises: [], tags: [],
    forbids: [].}

proc hasKey(ps: var PreambleStore; msgId: MessageId): bool {....raises: [],
    tags: [], forbids: [].}

proc init(T: typedesc[PeerSet]): T:type

proc init(T: typedesc[PreambleInfo]; preamble: ControlPreamble;
          sender: PubSubPeer; startsAt: Moment; expiresAt: Moment): T:type

proc init(T: typedesc[PreambleStore]): T:type

proc insert(ps: var PreambleStore; msgId: MessageId; info: PreambleInfo) {.
    ...raises: [], tags: [], forbids: [].}

proc len(ps: var PreambleStore): int {....raises: [], tags: [], forbids: [].}

proc popExpired(ps: var PreambleStore; now: Moment): Option[PreambleInfo] {.
    ...raises: [], tags: [], forbids: [].}

proc possiblePeersToQuery(preamble: PreambleInfo): seq[PeerId] {....raises: [],
    tags: [], forbids: [].}

template withValue(ps: var PreambleStore; key: MessageId; value, body: untyped)