code: public @Nonnull Iterable<Double> doubles() {
          final JsonArray parent=this;
          return () -> {
              final Iterator<JsonElement> iterator = parent.iterator();
              return new Iterator<Double>() {
  
                  @Override
                  public boolean hasNext() {
                      return iterator.hasNext();
                  }
  
                  @Override
                  public Double next() {
                      return iterator.next().asDouble();
                  }
  
                  @Override
                  public void remove() {
                      iterator.remove();
                  }
              };
          };
      }
docs: Convenience method to prevent casting JsonElement to Double when iterating in the common case that you have
  an array of doubles.
  
  @return iterable that iterates over Doubles instead of JsonElements.