R devel - Nov 2009 - Calling default method for primitive functions

Hi all,

How can I call the default method of a S3 object defined by a
primitive method?   i.e. in the following example, how do I call the
default [ method instead of the one I defined for the class.

new_a <- function(x) structure(x, class = "a")

a <- new_a(1:5)

"[.a" <- function(x, i, j, ...) {
  new_a(x[, j, ])
}

a[, 5]

Thanks,

Hadley

-- 
http://had.co.nz/

On Nov 23, 2009, at 16:00 , Hadley Wickham wrote:
> Hi all,
>
> How can I call the default method of a S3 object defined by a
> primitive method?   i.e. in the following example, how do I call the
> default [ method instead of the one I defined for the class.
>
> new_a <- function(x) structure(x, class = "a")
>
> a <- new_a(1:5)
>
> "[.a" <- function(x, i, j, ...) {
>  new_a(x[, j, ])
What about
new_a(unclass(x)[, j,])

Cheers,
Simon

> }
>
> a[, 5]
>
> Thanks,
>
> Hadley
>
> -- 
> http://had.co.nz/
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>
>

See ?.subset

On Mon, Nov 23, 2009 at 4:00 PM, Hadley Wickham <hadley at rice.edu>
wrote:
> Hi all,
>
> How can I call the default method of a S3 object defined by a
> primitive method? ? i.e. in the following example, how do I call the
> default [ method instead of the one I defined for the class.
>
> new_a <- function(x) structure(x, class = "a")
>
> a <- new_a(1:5)
>
> "[.a" <- function(x, i, j, ...) {
> ?new_a(x[, j, ])
> }
>
> a[, 5]

Perfect - thanks!
Hadley

On Mon, Nov 23, 2009 at 5:22 PM, Gabor Grothendieck
<ggrothendieck at gmail.com> wrote:
> See ?.subset
>
> On Mon, Nov 23, 2009 at 4:00 PM, Hadley Wickham <hadley at rice.edu>
wrote:
>> Hi all,
>>
>> How can I call the default method of a S3 object defined by a
>> primitive method? ? i.e. in the following example, how do I call the
>> default [ method instead of the one I defined for the class.
>>
>> new_a <- function(x) structure(x, class = "a")
>>
>> a <- new_a(1:5)
>>
>> "[.a" <- function(x, i, j, ...) {
>> ?new_a(x[, j, ])
>> }
>>
>> a[, 5]
>
>


-- 
http://had.co.nz/