>> 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,])That's what I'm currently using, but I'm concerned about the performance implications - won't that create a copy of x? Hadley -- http://had.co.nz/ ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
