[Rcpp-devel] RInside destructor not working properly?

[Christian Sigg]

Dear Dirk

Thank you for the reply (and for Rcpp and RInside).

> | Question: Is the RInside destructor not working properly? I would have expected that both in foo() and bar(), an instance of R is created and then destroyed| immediately, without producing any kind of output.
> 
> No, wrong setup. R is single-threaded, and you can have only
> precisely __ONE__ instance of R in your program. You have two.

I was not aware that two instances of R are active at the same time. It was my expectation that by instantiating the RInside class as a local variable, at the end of foo() the destructor R.~RInside() would be called and the encapsulated R instance would be terminated, before a new one is instantiated in bar(). 

I did take a cursory glance at the implementation of ~RInside() before asking the question, and the function call

Rf_endEmbeddedR(0);

gave me that (wrong) impression. I don't know the R implementation internals.

> Create one in main() and pass references around.


Is it possible to terminate the RInside instance instead, and later start a new one? I don't think that it is proper to modify main() with the unit testing framework that I'm using (gtest), as the tests are discovered without explicitly calling them from main().

Regards
Christian