The function dspec-subclass-p
determines whether the dspec class denoted by class1 is a subclass of that denoted by class2.
CL-USER 55 > (dspec:dspec-subclass-p 'defmacro 'type)
NIL
CL-USER 56 > (dspec:dspec-subclass-p 'defmacro
'function)
T
LispWorks User Guide and Reference Manual - 13 Feb 2015