lessThanByWeight

        fn lessThanByWeight(
            weights: [256]u4,
            lhs: PrefixedSymbol,
            rhs: PrefixedSymbol,
        ) bool {
            // NOTE: this function relies on the use of a stable sorting algorithm,
            //       otherwise a special case of if (weights[lhs] == weights[rhs]) return lhs < rhs;
            //       should be added
            return weights[lhs.symbol] < weights[rhs.symbol];
        }