[Rcpp-devel] R_PreserveObject and R_ReleaseObject

[Simon Dirmeier]

Thanks Dirk and Kevin. That cleared a lot of things up.

Best,
Simon

Am 16.08.18 um 17:52 schrieb Dirk Eddelbuettel:
> On 16 August 2018 at 08:43, Kevin Ushey wrote:
> | I think the main problem is that it's easy to use your class incorrectly.
> | For example:
> |
> | - What happens if your map is destructed? The SEXPs it is handling are
> | effectively leaked.
> | - What if you copy your map? Since SEXPs are pointers, you now have two
> | maps containing the same pointers, and if you were to attempt to remove a
> | SEXP from both maps problems would occur.
> |
> | Rather than attempting to manage the lifetime of these R objects in your
> | map's methods, it's better to have wrapper classes that manage the lifetime
> | of a single SEXP -- ie, what Rcpp does with its classes.
> |
> | You might consider just using e.g. std::unordered_map<T, Rcpp::RObject> if
> | you need to map some arbitrary types to R objects.
>
> +1, or "what he said" which I generally have on auto-loop for Kevin anyway ...
>
> Dirk
>