code: @SuppressWarnings("unchecked")
      public ScoredValue<V> mapScore(Function<? super Number, ? extends Number> mapper) {
  
          LettuceAssert.notNull(mapper, "Mapper function must not be null");
  
          if (hasValue()) {
              return new ScoredValue<V>(mapper.apply(score).doubleValue(), getValue());
          }
  
          return this;
      }
docs: Returns a {@link ScoredValue} consisting of the results of applying the given function to the score of this element.
  Mapping is performed only if a {@link #hasValue() value is present}.
  
  @param mapper a stateless function to apply to each element
  @return the new {@link ScoredValue}