[R] Factor names & levels

[Damon Wischik]

> names() is only defined for vectors and lists and factors are
> neither.  See ?vector and ?names for more info.

?vector tells me that factors are not vectors, but ?names does not tell me
that names() is only defined for vectors and lists. If it were, how
should I understand the following?

> x <- factor(c("one","three"))
> names(x) <- c("fred","jim")
> names(x)
[1] "fred" "jim" 
> class(x)
[1] "factor"