Function for_each_record_calls 

pub fn for_each_record_calls<F>(
    input: &Path,
    config: &ScanConfig,
    call_params: &CallParams,
    greedy: bool,
    on_record: F,
) -> Result<RunStats>
where
    F: FnMut(&str, &[u8], &[NucleosomeCall], usize) -> Result<()>,

Score every record and hand its nucleosome calls to on_record, with the sequence.

Calls need two things the per-score path does not provide: the record’s bases, for the sequence the reference puts in the GFF attribute column, and every call for a record at once, because the greedy selection ranks them against each other. Both are per record, so this reads whole records rather than windows even when an index is available.

Only dyads that actually score are retained, which is a small fraction of positions, so what is held is the calls for one record rather than its scores.