code: func TagPairs(tagPairs []*TagPair) func(*Game) {
  	return func(g *Game) {
  		g.tagPairs = append([]*TagPair(nil), tagPairs...)
  	}
  }
docs: // TagPairs returns a function that sets the tag pairs
  // to the given value.  The returned function is designed
  // to be used in the NewGame constructor.