[R] assigning NULL to a list element

[Hadley Wickham]

On Fri, Feb 17, 2012 at 7:51 PM, Benilton Carvalho
<beniltoncarvalho at gmail.com> wrote:
> Hi everyone,
>
> For reasons beyond the scope of this message, I'd like to append a
> NULL element to the end of a list.
>
> tmp0 <- list(a=1, b=NULL, c=3)
> append(tmp0, c(d=4)) ## works as expected
> append(tmp0, c(d=NULL)) ## list with a/b/c only
>
> Given that I could use
>
> tmp0$a <- NULL
>
> to remove 'a', I seem to understand why appending NULL returns me the
> original list... But how should I proceed to actually have d=NULL
> (just like I have 'b' in tmp0 above)?

tmp0["d"] <- list(NULL)

?

Hadley

-- 
Assistant Professor / Dobelman Family Junior Chair
Department of Statistics / Rice University
http://had.co.nz/