How do I check if a list or dict is empty in EK9?

  if myList is empty
    stdout.println("No items")

  count <- length myList

  if ~myList is empty
    stdout.println("Has items")

defines module qa.collectiontasks.emptycheck

  defines function
    getList()
      <- rtn as List of Integer: List() of Integer

  defines program
    CollectionEmptyDemo()
      stdout <- Stdout()

      // === LIST IS EMPTY ===

      emptyList <- getList()
      stdout.println(`Empty list is empty: ${emptyList is empty}`)
      stdout.println(`Empty list length: ${length emptyList}`)

      filledList <- [1, 2, 3]
      stdout.println(`Filled list is empty: ${filledList is empty}`)
      stdout.println(`Filled list length: ${length filledList}`)

      // === DICT IS EMPTY ===

      emptyDict <- Dict() of (String, Integer)
      stdout.println(`Empty dict is empty: ${emptyDict is empty}`)
      stdout.println(`Empty dict length: ${length emptyDict}`)

      filledDict <- {"a": 1, "b": 2}
      stdout.println(`Filled dict is empty: ${filledDict is empty}`)
      stdout.println(`Filled dict length: ${length filledDict}`)

      // === IS NOT EMPTY ===

      if ~filledList is empty
        stdout.println("Filled list has items")

      if emptyList is empty
        stdout.println("Empty list has no items")

      // === CRITICAL: EMPTY IS SET ===

      // Empty list IS set — it is a valid, meaningful value
      require emptyList?
      stdout.println(`Empty list isSet: ${emptyList?}`)

      // Empty dict IS set
      require emptyDict?
      stdout.println(`Empty dict isSet: ${emptyDict?}`)

      // === STRING EMPTY CHECK ===

      emptyStr <- ""
      fullStr <- "Hello"
      stdout.println(`Empty string is empty: ${emptyStr is empty}`)
      stdout.println(`Full string is empty: ${fullStr is empty}`)

emptyList.isEmpty()

emptyList is empty

filledList.size()

length filledList