This returns a two-element list describing the method implementations used to implement the current (TclOO) call chain. The first element is the same as would be reported by info object call for the current method (except that this also reports useful values from within constructors and destructors, whose names are reported as <constructor> and <destructor> respectively), and the second element is an index into the first element's list that indicates which actual implementation is currently executing (the first implementation to execute is always at index 0).