Rectangle for reduce

CesiumJS
1

Is there a good way to get a starting Rectangle that can be used with Array.reduce? I have a list of multiple of rectangles that I would like to get the union of.

I tried starting off with the following rectangle with the opposite of the max values but it doesn’t work as expected because Rectagle.union adds TWO_PI in some cases.

const empty = new Rectangle(
  Rectangle.MAX_VALUE.east,
  Rectangle.MAX_VALUE.south,
  Rectangle.MAX_VALUE.west,
  Rectangle.MAX_VALUE.north,
);

See this sandcastle for the full example

2

Ended up not providing a starting value and checking if there were actually items to reduce first.

const result = rectangles.length > 0 ? 
  rectangles.reduce((previous, current) => Rectangle.union(previous, current)) :
  undefined;

See sandcastle.