"function" when
functions are to be stored and used as method definitions.setMethod creates an object of this class. It's
unwise to create them directly. The class "SealedMethodDefinition" is created by a call to
setMethod with argument sealed = TRUE. It has
the same representation as "MethodDefinition".
"function", from data part.
Class "PossibleMethod", directly.
Class "OptionalMethods", by class "function".target slot is the class signature for which the method will
be dispatched, and the defined slot the signature for which
the method was originally specified (that is, the one that appeared
in some call to setMethod).MethodsList for the objects
defining sets of methods associated with a particular generic
function. The individual method definitions stored in these objects
are from class MethodDefinition, or an extension.
Class MethodWithNext for an extension used by
callNextMethod.