 
 /// This extension adds some useful functions to NSPointerArray.
 /// https://marcosantadev.com/swift-arrays-holding-elements-weak-references/
-extension NSPointerArray {
+public extension NSPointerArray {
     /// Adds an object to the array.
     ///
     /// - Parameter object: Object to be added.
-    func add(_ object: AnyObject?) {
+    public func add(_ object: AnyObject?) {
         guard let strongObject = object else {
             return
         }

    /// - Parameters:
    ///   - index: Index.
    ///   - object: Replacing object.
    func replace(at index: Int, with object: AnyObject?) {
        guard index < count, let strongObject = object else {
            return
        }

    ///
    /// - Parameter index: Index.
    /// - Returns: Returns an object at index.
    public func object(at index: Int) -> AnyObject? {
        guard index < count, let pointer = self.pointer(at: index) else {
            return nil
        }
