The local macro
returns a value which can be passed to invoke to call a method in the superclass of the current method definition (like
in Objective-C). When used within a define-objc-method form, instance methods in the superclass are invoked and when used within a define-objc-class-method form, class methods are invoked. The
has dynamic extent and it is an error to use
in any other contexts.
LispWorks Objective-C and Cocoa Interface User Guide and Reference Manual - 15 Dec 2011