for them: In addition, is.name
is a synonym for is.symbol
dispatches methods for the latter. Similarly, as.numeric
is a synonym for as.double
and dispatches methods for the
latter, i.e., S3 methods are for as.double
, whereas S4 methods
are to be written for as.numeric
Note that all of the group generic functions are also internal/primitive and allow methods to be written for them.
is a character vector listing the
primitives which are internal generic and not group generic.
are the internal
non-primitive functions which are internally generic.
For efficiency, internal dispatch only occurs on objects, that
is those for which is.object
for the methods which are available.