A specializer is a generalization of a class. A specializer is any one of the following:
A specializer may be used in many contexts where a class is required,
specifically, as a method specializer (hence the name), as the second
subclass?, and elsewhere.
Returns a list of the classes in specializer. If specializer is a class, the result is a list of that class. If specializer is a record type, the result is a list of the record type's class. If specializer is a union specializer, the result is a list of the component classes of the specializer.
#tif specializer1 and specializer2 are equivalent, otherwise returns
#f. Two specializers are equivalent if the lists returned by
specializer-classescontain the same elements.
Returns a union specializer consisting of the union of the classes of the arguments. This is equivalent to converting all of the specializer arguments to sets of classes, then taking the union of those sets.
#tif object is a union specializer, otherwise returns
#tif object is a list of specializers, otherwise returns