A set of methods that controllers and UI elements can implement to manage editing.
The NSEditor informal protocol provides a means for requesting that the receiver commit or discard any pending edits.
These methods are typically invoked on user interface elements by a controller. They can also be sent to a controller in response to a user’s attempt to save a document or quit an application.
NSController provides an implementation of this protocol, as do the AppKit user interface elements that support binding.