Function remember 

pub fn remember(
    cfg: &LeanConfig,
    refs: &[ChunkRef],
    entries: &BTreeMap<String, LeanEntry>,
)

Record the aliases of a whole document’s chunks, which a full load and a whole-document write hold every entry of, and keep this prefix’s cache to those chunks. A process that has loaded or written a document then answers “who cites this handle” without parsing a chunk.