Function expr::compare_columns

pub fn compare_columns<F>(
    order: &[ColumnOrder], 
    left: &[Datum<'_>], 
    right: &[Datum<'_>], 
    tiebreaker: F
) -> Ordering where
    F: Fn() -> Ordering, 

Compare left and right using order. If that doesn’t produce a strict ordering, call tiebreaker.