[Rcpp-devel] error: wrap is not a template function

[Fabio Tordini]

Hi Dirk,
I actually supplied a definition, right after the class implementation, 
as I wrote before:

// DECLARATION
class SamData {
     // CLASS IMPLEMENTATION
};

// WRAP / AS DEFINITION
namespace Rcpp {
template<> SEXP wrap(const SamData &s) {
    return Rcpp::List::create( Rcpp::Named("Chr1") = s.getChr1(),
                               Rcpp::Named("Chr2") = s.getChr2(),
                               Rcpp::Named("Seq1") = s.getSeq(),
                               Rcpp::Named("HS1")  = s.getHS1(),
                               Rcpp::Named("HS2")  = s.getHS2(),
                               Rcpp::Named("Id")   = s.getId(),
                               Rcpp::Named("Start1") = s.getStart1(),
                               Rcpp::Named("Start2") = s.getStart2() );
}
template <> SamData as( SEXP s ) {
     Rcpp::List samL(s);
     SamData sam;
     sam.setChr1( Rcpp::as<std::string>(samL["Chr1"]) );
     sam.setChr2( Rcpp::as<std::string>(samL["Chr2"]) );
     sam.setSeq( Rcpp::as<std::string>(samL["Seq1"]) );
     sam.setHS1( Rcpp::as<size_t>(samL["HS1"]) );
     sam.setHS2( Rcpp::as<size_t>(samL["HS2"]) );
     sam.setStart1( Rcpp::as<long>( samL["Start1"]) );
     sam.setStart2( Rcpp::as<long>( samL["Start2"]) );
     sam.setId( Rcpp::as<long>( samL["Id"]) );

     return sam;
}

} // NAMESPACE RCPP


I thought this would be suffice to define a template specialisation for 
'as' and 'wrap'. Also, this solution works as expected in a GSL-free 
context.

Am I doing something wrong here?


Fabio




On 05/21/2015 05:41 PM, Dirk Eddelbuettel wrote:
>
> On 21 May 2015 at 17:17, Fabio Tordini wrote:
> | while extending Rcpp with my C++ classes, I received hundreds of "
> | 'wrap' is not a template function" and " 'as' is not a template
> | function" errors when compiling. Beside this, I get an impressive list
> | of errors referring to RcppGSL files.
> |
> | The library from which my classes come from makes use GSL (on C++ side),
> | thus I link RcppGSL to my package.
> |
> | Here is my extending for one class:
> | #ifndef SAMDATA_HPP_
> | #define SAMDATA_HPP_
> |
> | class SamData;
> |
> | #include <RcppCommon.h>
> |
> | namespace Rcpp {
> |      template<> SEXP wrap(const SamData &s);
> |      template<> SamData as( SEXP s ) ;
> | }
>
> That is a declaration. You also need to supply definitions.
>
> Dirk
>