LispWorks User Guide and Reference Manual > 14 The Metaobject Protocol > 14.1 Metaobject features incompatible with AMOP


14.1.8 Compatible metaclasses

The AMOP defines that the standard primary method for validate-superclass should return true if the class of one of the arguments is standard-class and the class of the other is funcallable-standard-class .

In LispWorks, objects of these metaclasses are not completely compatible, so validate-superclass will return false in these cases.

Beware that defining a class that mixes standard-class and funcallable-standard-class can lead to inconsistencies with the predicate functionp , the type function and the class function .

LispWorks User Guide and Reference Manual - 22 Dec 2009