         attachment: NSTextAttachment,
         imageFor url: URL,
         onSuccess success: @escaping (UIImage) -> (),
-        onFailure failure: @escaping () -> ()) -> UIImage {
+        onFailure failure: @escaping () -> ()) {
         
         guard let textAttachmentDelegate = textAttachmentDelegate else {
             fatalError("This class requires a text attachment delegate to be set.")
         }
         
-        return textAttachmentDelegate.textView(self, attachment: attachment, imageAt: url, onSuccess: success, onFailure: failure)
-    }
-
-    func storage(_ storage: TextStorage, missingImageFor attachment: NSTextAttachment) -> UIImage {
+        textAttachmentDelegate.textView(self, attachment: attachment, imageAt: url, onSuccess: success, onFailure: failure)
+    }
+
+    func storage(_ storage: TextStorage, placeholderFor attachment: NSTextAttachment) -> UIImage {
         guard let textAttachmentDelegate = textAttachmentDelegate else {
             fatalError("This class requires a text attachment delegate to be set.")
         }
-        return textAttachmentDelegate.textView(self, placeholderForAttachment: attachment)
+
+        return textAttachmentDelegate.textView(self, placeholderFor: attachment)
     }
     
     func storage(_ storage: TextStorage, urlFor imageAttachment: ImageAttachment) -> URL {

    ///     - success: when the image is obtained, this closure should be executed.
    ///     - failure: if the image cannot be obtained, this closure should be executed.
    ///
    /// - Returns: the placeholder for the requested image.  Also useful if showing low-res versions
    ///         of the images.
    ///
    func textView(_ textView: TextView,
                  attachment: NSTextAttachment,
                  imageAt url: URL,
                  onSuccess success: @escaping (UIImage) -> Void,
                  onFailure failure: @escaping () -> Void) -> UIImage

    /// Called when an attachment is about to be added to the storage as an attachment (copy/paste), so that the
    /// delegate can specify an URL where that attachment is available.

    /// - Parameters:
    ///   - textView: the textview that is requesting the image
    ///   - attachment: the attachment that does not an have image source
    ///
    /// - Returns: an UIImage to represent the attachment graphically
    ///
    func textView(_ textView: TextView, placeholderFor attachment: NSTextAttachment) -> UIImage

    /// Called after a attachment is removed from the storage.
    ///
