| is.object {base} | R Documentation | 
A function rather for internal use.  It returns TRUE if the
object x has the R internal OBJECT attribute set, and
FALSE otherwise.
is.object(x)
x | 
object to be tested. | 
is.object is generic: you can write methods to handle
specific classes of objects, see InternalMethods.
is.object(1) # FALSE is.object(as.factor(1:3)) # TRUE