Function join_at_entry 

pub fn join_at_entry<C>(
    reader: &MarkerReader,
    catalog: &mut C,
    event_seq_before: u64,
) -> Result<Vec<JoinedStream>, EventStoreError>
where
    C: ReplayCatalog + ?Sized,

Joins folded marker cursors at event_seq_before to replayable catalog rows.

Quote, trade, and bar streams plan and load catalog slices from the beginning of the catalog through the folded cursor’s ts_init_hi, then return the first count rows. Order-book streams remain order-only and return no catalog rows.

Errors

Returns EventStoreError when marker cursor folding fails, when a folded slot has no dictionary entry, when count does not fit in memory on this platform, or when the catalog fails while planning or loading a replayable slice.