split.data.frame

Romain Francois wrote:

Hello,

I very much enjoy "with" and "subset" semantics for data frames and
was wondering if we could have something similar with split, basically
by evaluating the second argument "with" the data frame :

I seem to recall that this idea was considered and rejected when the
current split.data.frame was written (10 years ago!). The main reasons
were that

- it's not really THAT hard to evaluate a single splitting expression
using with() or eval()

- not all applications will have the splitting factor inside the df to
split ( split(df[-1], df[[1]]) for a simple case)

- if you need a computed splitting factor, there's a risk of inadvertent
variable capture. I.e., if you inside a function do

....
grp <- ...whatever...
spl <- split(x, grp)
....

and x has a variable called grp, what do you get?