Guillaume Yziquel wrote:
Laurent Gautier a écrit :
It does not have to be a functional language.
To see it in use within a some-language-to-R bridge, you can check the
source in JRI, rpy2.
I can mostly speak for rpy2, and the way it is done there relies on
both R and Python's GC. Creating a anonymous R object presented to the
Python world is first "R_preserved" (from garbage collection from R)
then using Python's reference counting mechanism, calling an
"R_Release" whenever the Python wrapper is available for garbage
collection (in fact there is a twist, but this is roughly the way it
is working). In your case, you'll use the OCaml GC system (and
"R_release" the R object when its OCaml representation is going for
garbage collection).
For now, garbage collection is a secondary issue.
I would have been interested in a binding to a functional language to
see exactly where you get a closure to closure mapping. That's why I was
asking since that's what I'm foremost interested in.
By low-level, I mean a binding that takes hold of R objects without
using symbols all over to reference them. (Using symbols in the
formals, the body or the environment of a closure is fine, for
instance, but I'd like to execute a closure directly, and eventually
be able to construct R closure from OCaml functions).
Rpy2 can do a lot of that, and probably so can JRI.
An anonymous closure to anonymous closure mapping? Could you point out
where this is done exactly?
Anonymous R objects, that is without an associated symbol in R, can be
passed to functions (and in that way makes a binding "take hold of R
objects without using symbols").
For example, building R code made of anonymous objects can be achieved
by making a LANGSXP object and tweaking it.
Example in R itself:
> x <- call("round", 2.3)
> eval(x)
[1] 2
> x[[1]] <- function(x) x^2
> eval(x)
[1] 5.29
Getting more complex constructs may need a little more trickery.
...or do you mean something else ?
L.
______________________________________________
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel
