Best way to use c++ code from R package FOO in package BAR

Question

I am trying to define a function using Rcpp for speedup. The situation is as follows:

• I have a package FOO with a lot of C++ code (my own package and currently not

Answer 1

Another option, in case you don't mind introducing Rcpp into package FOO - follow along with Section 3.5 of Rcpp-attributes and do the following:

1. Place // [[Rcpp::interfaces(cpp)]] at the top of the .cpp source files containing functions you'd like to be made available to other packages,

2. Place // [[Rcpp::export]] in front of those functions you would like exported,

3. Call compileAttributes() in the package directory of FOO to generate files in inst/include that can then be used by package BAR, using // [[Rcpp::depends(FOO)]],

4. Install package FOO.

If you have this set up correctly, you should be able to call a function with a template like this (supposing foo_a is an exported function from FOO):

// [[Rcpp::depends(FOO)]]

#include 
#include 
using namespace Rcpp;

// [[Rcpp::export]]
SEXP some_function() {
  return FOO::foo_a();
}