[R] dumping/loading objects with 'tsp' attribute

[Antonio, Fabio Di Narzo]

Dear all,
I'm indirectly faced with the fact that setting the 'tsp' attribute of
an object modifies its class definition:
> class( structure(1:2, tsp=c(1,2,1), class=c("myts","ts")) )
[1] "ts"   "myts"

In general, this is of really little (ok, I admit: totally no)
interest for me because 'myts' class is added just after assigning the
'tsp' attribute (by calling ts).
However, this behaviour gives me troubles when re-loading a previously
deparsed object, so that:
> x <- ts(1:2)
> class(x) <- c("myts", class(x))
> dput( x , "temp.dat")
> class(dget("temp.dat"))
[1] "ts"   "myts"
> unlink("temp.dat")

In other words, my real problem should be restated as: how to safely
dump (and then load) an object which has a (perhaps valid) "tsp"
attribute?
More generally: can someone suggest me a safer way to dump/restoring R objects?

Tnx all,
Antonio.
-- 
Antonio, Fabio Di Narzo
Ph.D. student at
Department of Statistical Sciences
University of Bologna, Italy