NULL
objects.
null() as.null(x) is.null(x)
null
and
as.null
always return
NULL
.
is.null
returns
TRUE
or
FALSE
,
according as
x
is or is not
NULL
.
Both
is.null
and
as.null
are generic; currently there are
no methods defined for either of them.
An object can be of length
0
and not be
NULL
, see the examples section.
is.null(character(0)) # returns FALSE