[Rcpp-devel] wrap

[Romain Francois]

Hi,

I've finally discovered the is_convertible type trait (from tr1 or 
C++0x) which helps closing the implementation of wrap.

Here are the types that can currently be wrapped

int
size_t
double
bool
std::string
const char* const
Rbyte
Rcomplex

Additionally, if the type T can be wrapped, then the following types can 
also be wrapped:

std::vector<T>
std::deque<T>
std::list<T>
std::set<T>
std::multiset<T>
std::map<std::string,T>
std::multimap<std::string,T>

std::tr1::unordered_set<T>
std::tr1::unordered_map<std::string,T>
std::tr1::unordered_multimap<std::string,T>

Additionally, type Foo can be wrapped if it can be implicitely converted 
to SEXP, which we can identify at compile time with is_convertible.

Note that you can compose in any way you want, so for example:

std::vector< std::map<std::string,std::vector<int> > >

will happily be wrapped into a list of named lists of integer vectors. 
There are examples of this in the unit test runit.wrap.R. The 
implementation of this is contained in the Rcpp/internal/wrap.h file.

Romain

-- 
Romain Francois
Professional R Enthusiast
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http://romainfrancois.blog.free.fr
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