public int getRerankCount() {
        if (rerankCount >= 0) return rerankCount;
        return uniquelyInherited(RankProfile::getRerankCount, c -> c >= 0, "rerank-count").orElse(-1);
    }
Returns a read only map view of the rank properties to use in this profile. This is never null.
config-model/src/main/java/com/yahoo/schema/RankProfile.java