Dear maintainers #1 a user-defined allocate-instance method is not called at all #2 slot-missing is called with a slot-name of nil #3 update-dependent is not being applied to its keyword arguments Best regards William "1.2.1" "Java_HotSpot(TM)_Client_VM-Oracle_Corporation-1.7.0_17-b02" "x86-Windows_7-6.1" ;;;#1 CL-USER(2): (defclass quux-class (standard-class) ()) #<STANDARD-CLASS QUUX-CLASS {D2A36B}> CL-USER(3): (defmethod allocate-instance :after ((class quux-class) &rest initargs) (format t "allocated ~S~%" class)) #<STANDARD-METHOD ALLOCATE-INSTANCE :AFTER (QUUX-CLASS) {14A0B92}> CL-USER(4): (defclass quux nil (bar) (:metaclass quux-class)) #<QUUX-CLASS QUUX {50039B}> CL-USER(5): (make-instance *) #<QUUX {B2D899}> CL-USER(6): (inspect (fdefinition 'allocate-instance)) 0 LAYOUT -----------> #<LAYOUT {BEF803}> 1 NAME -------------> ALLOCATE-INSTANCE 2 LAMBDA-LIST ------> (CLASS &REST ...) 3 REQUIRED-ARGS ----> (CLASS) 4 OPTIONAL-ARGS ----> NIL 5 INITIAL-METHODS --> NIL 6 METHODS ----------> (#<STANDARD-METHOD ALLOCATE-INSTANCE :AFTER (QUUX-CLASS) {14A0B92}> #<STANDARD-METHOD ALLOCATE-INSTANCE :BEFORE (CLASS) {18C9692}> ...) 7 METHOD-CLASS -----> #<STANDARD-CLASS STANDARD-METHOD {A801B0}> 8 %METHOD-COMBINATION -> #<METHOD-COMBINATION STANDARD {F167BB}> 9 ARGUMENT-PRECEDENCE-ORDER -> (CLASS) 10 DECLARATIONS -----> NIL 11 CLASSES-TO-EMF-TABLE -> #<EQUAL HASH-TABLE 0 entries, 11 buckets {D15EE4}> 12 %DOCUMENTATION ---> NIL ;;;#2 CL-USER(11): (make-instance 'quux) #<QUUX {F2AE7E}> CL-USER(12): (slot-value * 'baz) #<THREAD "interpreter" {1A2FE4D}>: Debugger invoked on condition of type SIMPLE-ERROR The slot NIL is missing from the class #<QUUX-CLASS QUUX {50039B}>. Restarts: 0: TOP-LEVEL Return to top level. ;;;#3 CL-USER(2): (defclass foo-class (standard-class) ()) #<STANDARD-CLASS FOO-CLASS {14A123F}> CL-USER(3): (defclass foo-dep () ()) #<STANDARD-CLASS FOO-DEP {145B486}> CL-USER(4): (defmethod mop:update-dependent ((class foo-class) (dep foo-dep) &key direct-slots &allow-other-keys)) #<STANDARD-METHOD MOP:UPDATE-DEPENDENT (FOO-CLASS FOO-DEP) {155388B}> CL-USER(5): (defclass foo () (bar) (:metaclass foo-class)) #<FOO-CLASS FOO {25D10A}> CL-USER(6): (mop:add-dependent * (make-instance 'foo-dep)) (#<FOO-DEP {F167BB}>) CL-USER(7): (trace mop:update-dependent) (MOP:UPDATE-DEPENDENT) CL-USER(8): (defclass foo () (bar baz) (:metaclass foo-class)) 0: (MOP:UPDATE-DEPENDENT #<FOO-CLASS {25D10A}> #<FOO-DEP {F167BB}> (:DIRECT-SUPERCLASSES NIL :DIRECT-SUPERCLASSES NIL DIRECT-SLOTS ((:NAME BAR) (:NAME BAZ)))) #<THREAD "interpreter" {886140}>: Debugger invoked on condition of type PROGRAM-ERROR Odd number of keyword arguments. Restarts: 0: TOP-LEVEL Return to top level.