[Rcpp-devel] using Rcpp modules to expose class

| Hello,
| 
| I'm trying to expose 2 classes from a Rcpp module:
| 
| class Portfolio{
|   private:
|      std::string portfolioId, description;
|   public:
|       Portfolio(std::string portfolioId, std::string description)
|       : portfolioId(portfolioId), description(description) {}
|      
|       std::string getPortfolioId() {return portfolioId;} const
|       void setPortfolioId(const std::string&) {this->portfolioId =
| portfolioId;}
|      
|       std::string getDescription() {return description;} const
|       void setDescription(const std::string& description){this->description =
| description;}
| };
| 
| class PortfolioDataAccess{
|     private:
|     mongo::DBClientConnection c;
|    
|     public:
|     PortfolioDataAccess();
|     virtual Portfolio read(std::string portfolioId);
|     virtual void create(std::string portfolioId, std::string description);
|    
|   };
| 
| 
| 
| 
| RCPP_MODULE(riskceteraPortfolio) {
|   class_<riskcetera::Portfolio>( "Portfolio" )
|   .constructor<std::string, std::string>()

That works because we can convert "in" from SEXP to std::strings.

|   .method("id", &riskcetera::Portfolio::getPortfolioId)
|   .method("description", &riskcetera::Portfolio::getDescription)
|   ;
|  
| class_<riskcetera::PortfolioDataAccess>("PortfolioAccess")
|   .constructor()
|   .method("read", &riskcetera::PortfolioDataAccess::read)
|   ;
| } 
| 
| When trying to compile the module I get the following error:
| 
| 
| /riskcetera/home/aludin/R/x86_64-pc-linux-gnu-library/3.0/Rcpp/include/Rcpp/internal/wrap.h:474:7: error: no viable conversion from 'const riskcetera::Portfolio' to 'SEXP' (aka 'SEXPREC *')
|         SEXP x = object ; 

That is pretty plain:  You need to supply a wrap() converter that tells the
compiler how to turn one of your objects ("Portfolio") into R's standard
type, the SEXP.

The currently-on-CRAN version of RcpBDT may help you.  It does something
pretty simply with Boost Date_Time, converting dates between the Boost
representation and the Rcpp / R representation.  It uses custom as<>() and
wrap(), and exposes a handful of useful functions too.   [ And do look at the
CRAN version, the R-Forge version is in heavier development which I started
last fall and hope to get back to by the summer. ]
 
Dirk

Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com

Hi Dirk,

Thanks for your answer!

So if I understand correctly, the fact that I exposed previously 
Portfolio is not enough?
I still need to provide wrap the template specialization:

     template <> SEXP wrap( const Portfolio& ) ;

Thanks,

Anwar

On 13 May 2013 at 14:59, Anwar Ludin wrote:
| Hello,
|
| I'm trying to expose 2 classes from a Rcpp module:
|
| class Portfolio{
|   private:
|      std::string portfolioId, description;
|   public:
|       Portfolio(std::string portfolioId, std::string description)
|       : portfolioId(portfolioId), description(description) {}
|
|       std::string getPortfolioId() {return portfolioId;} const
|       void setPortfolioId(const std::string&) {this->portfolioId =
| portfolioId;}
|
|       std::string getDescription() {return description;} const
|       void setDescription(const std::string& description){this->description =
| description;}
| };
|
| class PortfolioDataAccess{
|     private:
|     mongo::DBClientConnection c;
|
|     public:
|     PortfolioDataAccess();
|     virtual Portfolio read(std::string portfolioId);
|     virtual void create(std::string portfolioId, std::string description);
|
|   };
|
|
|
|
| RCPP_MODULE(riskceteraPortfolio) {
|   class_<riskcetera::Portfolio>( "Portfolio" )
|   .constructor<std::string, std::string>()

That works because we can convert "in" from SEXP to std::strings.

|   .method("id", &riskcetera::Portfolio::getPortfolioId)
|   .method("description", &riskcetera::Portfolio::getDescription)
|   ;
|
| class_<riskcetera::PortfolioDataAccess>("PortfolioAccess")
|   .constructor()
|   .method("read", &riskcetera::PortfolioDataAccess::read)
|   ;
| }
|
| When trying to compile the module I get the following error:
|
|
| /riskcetera/home/aludin/R/x86_64-pc-linux-gnu-library/3.0/Rcpp/include/Rcpp/internal/wrap.h:474:7: error: no viable conversion from 'const riskcetera::Portfolio' to 'SEXP' (aka 'SEXPREC *')
|         SEXP x = object ;

That is pretty plain:  You need to supply a wrap() converter that tells the
compiler how to turn one of your objects ("Portfolio") into R's standard
type, the SEXP.

The currently-on-CRAN version of RcpBDT may help you.  It does something
pretty simply with Boost Date_Time, converting dates between the Boost
representation and the Rcpp / R representation.  It uses custom as<>() and
wrap(), and exposes a handful of useful functions too.   [ And do look at the
CRAN version, the R-Forge version is in heavier development which I started
last fall and hope to get back to by the summer. ]
  
Dirk

| Hi Dirk,
| 
| Thanks for your answer!
| 
| So if I understand correctly, the fact that I exposed previously 
| Portfolio is not enough?

What do you mean by "exposed"?    

You defined it, so the compiler will no
comlain about 'unknown type'.  But that alone doesn't get it over to R.

| I still need to provide wrap the template specialization:
| 
|      template <> SEXP wrap( const Portfolio& ) ;

I think so, yes.

Dirk

 
| Thanks,
| 
| Anwar
|

| > | Hello,
| > |
| > | I'm trying to expose 2 classes from a Rcpp module:
| > |
| > | class Portfolio{
| > |   private:
| > |      std::string portfolioId, description;
| > |   public:
| > |       Portfolio(std::string portfolioId, std::string description)
| > |       : portfolioId(portfolioId), description(description) {}
| > |
| > |       std::string getPortfolioId() {return portfolioId;} const
| > |       void setPortfolioId(const std::string&) {this->portfolioId =
| > | portfolioId;}
| > |
| > |       std::string getDescription() {return description;} const
| > |       void setDescription(const std::string& description){this->description =
| > | description;}
| > | };
| > |
| > | class PortfolioDataAccess{
| > |     private:
| > |     mongo::DBClientConnection c;
| > |
| > |     public:
| > |     PortfolioDataAccess();
| > |     virtual Portfolio read(std::string portfolioId);
| > |     virtual void create(std::string portfolioId, std::string description);
| > |
| > |   };
| > |
| > |
| > |
| > |
| > | RCPP_MODULE(riskceteraPortfolio) {
| > |   class_<riskcetera::Portfolio>( "Portfolio" )
| > |   .constructor<std::string, std::string>()
| >
| > That works because we can convert "in" from SEXP to std::strings.
| >
| > |   .method("id", &riskcetera::Portfolio::getPortfolioId)
| > |   .method("description", &riskcetera::Portfolio::getDescription)
| > |   ;
| > |
| > | class_<riskcetera::PortfolioDataAccess>("PortfolioAccess")
| > |   .constructor()
| > |   .method("read", &riskcetera::PortfolioDataAccess::read)
| > |   ;
| > | }
| > |
| > | When trying to compile the module I get the following error:
| > |
| > |
| > | /riskcetera/home/aludin/R/x86_64-pc-linux-gnu-library/3.0/Rcpp/include/Rcpp/internal/wrap.h:474:7: error: no viable conversion from 'const riskcetera::Portfolio' to 'SEXP' (aka 'SEXPREC *')
| > |         SEXP x = object ;
| >
| > That is pretty plain:  You need to supply a wrap() converter that tells the
| > compiler how to turn one of your objects ("Portfolio") into R's standard
| > type, the SEXP.
| >
| > The currently-on-CRAN version of RcpBDT may help you.  It does something
| > pretty simply with Boost Date_Time, converting dates between the Boost
| > representation and the Rcpp / R representation.  It uses custom as<>() and
| > wrap(), and exposes a handful of useful functions too.   [ And do look at the
| > CRAN version, the R-Forge version is in heavier development which I started
| > last fall and hope to get back to by the summer. ]
| >   
| > Dirk
| >
| 
|

Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com

As suggested in the example of Romain's Blog 
here http://romainfrancois.blog.free.fr/
you need to define the class before "exposing" it and then implement it (I think it is also important that using namespace Rcpp  comes after the exposed stuff). 

class Foo ;
RCPP_EXPOSED_CLASS(Foo)

using namespace Rcpp ;

class Foo{
    public:
        enum Bla{ FOO, BAR } ;
... 


is it what you did ? 
I made it work in some cases and I did not have to implement the wrap (which is the whole purpose of module I think). 
R.

----- Mail original -----
De: "Anwar Ludin" <anwar.ludin at riskcetera.com>
?: "Dirk Eddelbuettel" <edd at debian.org>
Cc: rcpp-devel at lists.r-forge.r-project.org
Envoy?: Lundi 13 Mai 2013 16:11:35
Objet: Re: [Rcpp-devel] using Rcpp modules to expose class

Hi Dirk,

Thanks for your answer!

So if I understand correctly, the fact that I exposed previously 
Portfolio is not enough?
I still need to provide wrap the template specialization:

     template <> SEXP wrap( const Portfolio& ) ;

Thanks,

Anwar

On 13 May 2013 at 14:59, Anwar Ludin wrote:
| Hello,
|
| I'm trying to expose 2 classes from a Rcpp module:
|
| class Portfolio{
|   private:
|      std::string portfolioId, description;
|   public:
|       Portfolio(std::string portfolioId, std::string description)
|       : portfolioId(portfolioId), description(description) {}
|
|       std::string getPortfolioId() {return portfolioId;} const
|       void setPortfolioId(const std::string&) {this->portfolioId =
| portfolioId;}
|
|       std::string getDescription() {return description;} const
|       void setDescription(const std::string& description){this->description =
| description;}
| };
|
| class PortfolioDataAccess{
|     private:
|     mongo::DBClientConnection c;
|
|     public:
|     PortfolioDataAccess();
|     virtual Portfolio read(std::string portfolioId);
|     virtual void create(std::string portfolioId, std::string description);
|
|   };
|
|
|
|
| RCPP_MODULE(riskceteraPortfolio) {
|   class_<riskcetera::Portfolio>( "Portfolio" )
|   .constructor<std::string, std::string>()

That works because we can convert "in" from SEXP to std::strings.

|   .method("id", &riskcetera::Portfolio::getPortfolioId)
|   .method("description", &riskcetera::Portfolio::getDescription)
|   ;
|
| class_<riskcetera::PortfolioDataAccess>("PortfolioAccess")
|   .constructor()
|   .method("read", &riskcetera::PortfolioDataAccess::read)
|   ;
| }
|
| When trying to compile the module I get the following error:
|
|
| /riskcetera/home/aludin/R/x86_64-pc-linux-gnu-library/3.0/Rcpp/include/Rcpp/internal/wrap.h:474:7: error: no viable conversion from 'const riskcetera::Portfolio' to 'SEXP' (aka 'SEXPREC *')
|         SEXP x = object ;

That is pretty plain:  You need to supply a wrap() converter that tells the
compiler how to turn one of your objects ("Portfolio") into R's standard
type, the SEXP.

The currently-on-CRAN version of RcpBDT may help you.  It does something
pretty simply with Boost Date_Time, converting dates between the Boost
representation and the Rcpp / R representation.  It uses custom as<>() and
wrap(), and exposes a handful of useful functions too.   [ And do look at the
CRAN version, the R-Forge version is in heavier development which I started
last fall and hope to get back to by the summer. ]
  
Dirk

_______________________________________________
Rcpp-devel mailing list
Rcpp-devel at lists.r-forge.r-project.org
https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel

| As suggested in the example of Romain's Blog 
| here http://romainfrancois.blog.free.fr/

There are dozens of posts regarding Rcpp on his blog.  If you refer to one
such post, could you show us the relevant (and presumably still valid) URL?  

Otherwise we just don't know what you refer to.

| you need to define the class before "exposing" it and then implement it (I think it is also important that using namespace Rcpp  comes after the exposed stuff). 
| 
| class Foo ;
| RCPP_EXPOSED_CLASS(Foo)
| 
| using namespace Rcpp ;
| 
| class Foo{
|     public:
|         enum Bla{ FOO, BAR } ;
| ... 
| 
| 
| is it what you did ? 
| I made it work in some cases and I did not have to implement the wrap
| (which is the whole purpose of module I think). 

Modules help you with setters/getters of _components of a class you expose_
in such a declaration.

What Anwar wants here is different: he wants to pass the whole class as is.
For which conversion code has to come from somewhere: hence the need for wrap().

I could of course be misunderstanding the issue too..

Dirk


| R.
| 
| ----- Mail original -----
| De: "Anwar Ludin" <anwar.ludin at riskcetera.com>
| ?: "Dirk Eddelbuettel" <edd at debian.org>
| Cc: rcpp-devel at lists.r-forge.r-project.org
| Envoy?: Lundi 13 Mai 2013 16:11:35
| Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
| 
| Hi Dirk,
| 
| Thanks for your answer!
| 
| So if I understand correctly, the fact that I exposed previously 
| Portfolio is not enough?
| I still need to provide wrap the template specialization:
| 
|      template <> SEXP wrap( const Portfolio& ) ;
| 
| Thanks,
| 
| Anwar
|

| > | Hello,
| > |
| > | I'm trying to expose 2 classes from a Rcpp module:
| > |
| > | class Portfolio{
| > |   private:
| > |      std::string portfolioId, description;
| > |   public:
| > |       Portfolio(std::string portfolioId, std::string description)
| > |       : portfolioId(portfolioId), description(description) {}
| > |
| > |       std::string getPortfolioId() {return portfolioId;} const
| > |       void setPortfolioId(const std::string&) {this->portfolioId =
| > | portfolioId;}
| > |
| > |       std::string getDescription() {return description;} const
| > |       void setDescription(const std::string& description){this->description =
| > | description;}
| > | };
| > |
| > | class PortfolioDataAccess{
| > |     private:
| > |     mongo::DBClientConnection c;
| > |
| > |     public:
| > |     PortfolioDataAccess();
| > |     virtual Portfolio read(std::string portfolioId);
| > |     virtual void create(std::string portfolioId, std::string description);
| > |
| > |   };
| > |
| > |
| > |
| > |
| > | RCPP_MODULE(riskceteraPortfolio) {
| > |   class_<riskcetera::Portfolio>( "Portfolio" )
| > |   .constructor<std::string, std::string>()
| >
| > That works because we can convert "in" from SEXP to std::strings.
| >
| > |   .method("id", &riskcetera::Portfolio::getPortfolioId)
| > |   .method("description", &riskcetera::Portfolio::getDescription)
| > |   ;
| > |
| > | class_<riskcetera::PortfolioDataAccess>("PortfolioAccess")
| > |   .constructor()
| > |   .method("read", &riskcetera::PortfolioDataAccess::read)
| > |   ;
| > | }
| > |
| > | When trying to compile the module I get the following error:
| > |
| > |
| > | /riskcetera/home/aludin/R/x86_64-pc-linux-gnu-library/3.0/Rcpp/include/Rcpp/internal/wrap.h:474:7: error: no viable conversion from 'const riskcetera::Portfolio' to 'SEXP' (aka 'SEXPREC *')
| > |         SEXP x = object ;
| >
| > That is pretty plain:  You need to supply a wrap() converter that tells the
| > compiler how to turn one of your objects ("Portfolio") into R's standard
| > type, the SEXP.
| >
| > The currently-on-CRAN version of RcpBDT may help you.  It does something
| > pretty simply with Boost Date_Time, converting dates between the Boost
| > representation and the Rcpp / R representation.  It uses custom as<>() and
| > wrap(), and exposes a handful of useful functions too.   [ And do look at the
| > CRAN version, the R-Forge version is in heavier development which I started
| > last fall and hope to get back to by the summer. ]
| >   
| > Dirk
| >
| 
| 
| _______________________________________________
| Rcpp-devel mailing list
| Rcpp-devel at lists.r-forge.r-project.org
| https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel

Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com

http://romainfrancois.blog.free.fr/index.php?post/2012/10/25/Rcpp-modules-more-flexible
sorry about that
R.

----- Mail original -----
De: "Dirk Eddelbuettel" <edd at debian.org>
?: "Robin Girard" <robin.girard at mines-paristech.fr>
Cc: "Anwar Ludin" <anwar.ludin at riskcetera.com>, rcpp-devel at lists.r-forge.r-project.org, "Dirk Eddelbuettel" <edd at debian.org>
Envoy?: Lundi 13 Mai 2013 19:25:09
Objet: Re: [Rcpp-devel] using Rcpp modules to expose class

| As suggested in the example of Romain's Blog 
| here http://romainfrancois.blog.free.fr/

There are dozens of posts regarding Rcpp on his blog.  If you refer to one
such post, could you show us the relevant (and presumably still valid) URL?  

Otherwise we just don't know what you refer to.

| you need to define the class before "exposing" it and then implement it (I think it is also important that using namespace Rcpp  comes after the exposed stuff). 
| 
| class Foo ;
| RCPP_EXPOSED_CLASS(Foo)
| 
| using namespace Rcpp ;
| 
| class Foo{
|     public:
|         enum Bla{ FOO, BAR } ;
| ... 
| 
| 
| is it what you did ? 
| I made it work in some cases and I did not have to implement the wrap
| (which is the whole purpose of module I think). 

Modules help you with setters/getters of _components of a class you expose_
in such a declaration.

What Anwar wants here is different: he wants to pass the whole class as is.
For which conversion code has to come from somewhere: hence the need for wrap().

I could of course be misunderstanding the issue too..

Dirk


| R.
| 
| ----- Mail original -----
| De: "Anwar Ludin" <anwar.ludin at riskcetera.com>
| ?: "Dirk Eddelbuettel" <edd at debian.org>
| Cc: rcpp-devel at lists.r-forge.r-project.org
| Envoy?: Lundi 13 Mai 2013 16:11:35
| Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
| 
| Hi Dirk,
| 
| Thanks for your answer!
| 
| So if I understand correctly, the fact that I exposed previously 
| Portfolio is not enough?
| I still need to provide wrap the template specialization:
| 
|      template <> SEXP wrap( const Portfolio& ) ;
| 
| Thanks,
| 
| Anwar
|

| > | Hello,
| > |
| > | I'm trying to expose 2 classes from a Rcpp module:
| > |
| > | class Portfolio{
| > |   private:
| > |      std::string portfolioId, description;
| > |   public:
| > |       Portfolio(std::string portfolioId, std::string description)
| > |       : portfolioId(portfolioId), description(description) {}
| > |
| > |       std::string getPortfolioId() {return portfolioId;} const
| > |       void setPortfolioId(const std::string&) {this->portfolioId =
| > | portfolioId;}
| > |
| > |       std::string getDescription() {return description;} const
| > |       void setDescription(const std::string& description){this->description =
| > | description;}
| > | };
| > |
| > | class PortfolioDataAccess{
| > |     private:
| > |     mongo::DBClientConnection c;
| > |
| > |     public:
| > |     PortfolioDataAccess();
| > |     virtual Portfolio read(std::string portfolioId);
| > |     virtual void create(std::string portfolioId, std::string description);
| > |
| > |   };
| > |
| > |
| > |
| > |
| > | RCPP_MODULE(riskceteraPortfolio) {
| > |   class_<riskcetera::Portfolio>( "Portfolio" )
| > |   .constructor<std::string, std::string>()
| >
| > That works because we can convert "in" from SEXP to std::strings.
| >
| > |   .method("id", &riskcetera::Portfolio::getPortfolioId)
| > |   .method("description", &riskcetera::Portfolio::getDescription)
| > |   ;
| > |
| > | class_<riskcetera::PortfolioDataAccess>("PortfolioAccess")
| > |   .constructor()
| > |   .method("read", &riskcetera::PortfolioDataAccess::read)
| > |   ;
| > | }
| > |
| > | When trying to compile the module I get the following error:
| > |
| > |
| > | /riskcetera/home/aludin/R/x86_64-pc-linux-gnu-library/3.0/Rcpp/include/Rcpp/internal/wrap.h:474:7: error: no viable conversion from 'const riskcetera::Portfolio' to 'SEXP' (aka 'SEXPREC *')
| > |         SEXP x = object ;
| >
| > That is pretty plain:  You need to supply a wrap() converter that tells the
| > compiler how to turn one of your objects ("Portfolio") into R's standard
| > type, the SEXP.
| >
| > The currently-on-CRAN version of RcpBDT may help you.  It does something
| > pretty simply with Boost Date_Time, converting dates between the Boost
| > representation and the Rcpp / R representation.  It uses custom as<>() and
| > wrap(), and exposes a handful of useful functions too.   [ And do look at the
| > CRAN version, the R-Forge version is in heavier development which I started
| > last fall and hope to get back to by the summer. ]
| >   
| > Dirk
| >
| 
| 
| _______________________________________________
| Rcpp-devel mailing list
| Rcpp-devel at lists.r-forge.r-project.org
| https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel

Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com

| http://romainfrancois.blog.free.fr/index.php?post/2012/10/25/Rcpp-modules-more-flexible

Oh a good one indeed -- I had forgotten about that aspect (and in fact not
used it yet in a project of mine).

This may indeed work for Anwar, so thanks for the pointer.   

[ That said, I do like explicit code too and the control one has which
explicit converters does come on handy.  Also, his real class may well be
more complicated than the token example from the blog posts so things may or
may not work.  Proof is in the pudding and all that. ]

Dirk

| R.
| 
| ----- Mail original -----
| De: "Dirk Eddelbuettel" <edd at debian.org>
| ?: "Robin Girard" <robin.girard at mines-paristech.fr>
| Cc: "Anwar Ludin" <anwar.ludin at riskcetera.com>, rcpp-devel at lists.r-forge.r-project.org, "Dirk Eddelbuettel" <edd at debian.org>
| Envoy?: Lundi 13 Mai 2013 19:25:09
| Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
| 
|

| | As suggested in the example of Romain's Blog 
| | here http://romainfrancois.blog.free.fr/
| 
| There are dozens of posts regarding Rcpp on his blog.  If you refer to one
| such post, could you show us the relevant (and presumably still valid) URL?  
| 
| Otherwise we just don't know what you refer to.
| 
| | you need to define the class before "exposing" it and then implement it (I think it is also important that using namespace Rcpp  comes after the exposed stuff). 
| | 
| | class Foo ;
| | RCPP_EXPOSED_CLASS(Foo)
| | 
| | using namespace Rcpp ;
| | 
| | class Foo{
| |     public:
| |         enum Bla{ FOO, BAR } ;
| | ... 
| | 
| | 
| | is it what you did ? 
| | I made it work in some cases and I did not have to implement the wrap
| | (which is the whole purpose of module I think). 
| 
| Modules help you with setters/getters of _components of a class you expose_
| in such a declaration.
| 
| What Anwar wants here is different: he wants to pass the whole class as is.
| For which conversion code has to come from somewhere: hence the need for wrap().
| 
| I could of course be misunderstanding the issue too..
| 
| Dirk
| 
| 
| | R.
| | 
| | ----- Mail original -----
| | De: "Anwar Ludin" <anwar.ludin at riskcetera.com>
| | ?: "Dirk Eddelbuettel" <edd at debian.org>
| | Cc: rcpp-devel at lists.r-forge.r-project.org
| | Envoy?: Lundi 13 Mai 2013 16:11:35
| | Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
| | 
| | Hi Dirk,
| | 
| | Thanks for your answer!
| | 
| | So if I understand correctly, the fact that I exposed previously 
| | Portfolio is not enough?
| | I still need to provide wrap the template specialization:
| | 
| |      template <> SEXP wrap( const Portfolio& ) ;
| | 
| | Thanks,
| | 
| | Anwar
| |

| | > | Hello,
| | > |
| | > | I'm trying to expose 2 classes from a Rcpp module:
| | > |
| | > | class Portfolio{
| | > |   private:
| | > |      std::string portfolioId, description;
| | > |   public:
| | > |       Portfolio(std::string portfolioId, std::string description)
| | > |       : portfolioId(portfolioId), description(description) {}
| | > |
| | > |       std::string getPortfolioId() {return portfolioId;} const
| | > |       void setPortfolioId(const std::string&) {this->portfolioId =
| | > | portfolioId;}
| | > |
| | > |       std::string getDescription() {return description;} const
| | > |       void setDescription(const std::string& description){this->description =
| | > | description;}
| | > | };
| | > |
| | > | class PortfolioDataAccess{
| | > |     private:
| | > |     mongo::DBClientConnection c;
| | > |
| | > |     public:
| | > |     PortfolioDataAccess();
| | > |     virtual Portfolio read(std::string portfolioId);
| | > |     virtual void create(std::string portfolioId, std::string description);
| | > |
| | > |   };
| | > |
| | > |
| | > |
| | > |
| | > | RCPP_MODULE(riskceteraPortfolio) {
| | > |   class_<riskcetera::Portfolio>( "Portfolio" )
| | > |   .constructor<std::string, std::string>()
| | >
| | > That works because we can convert "in" from SEXP to std::strings.
| | >
| | > |   .method("id", &riskcetera::Portfolio::getPortfolioId)
| | > |   .method("description", &riskcetera::Portfolio::getDescription)
| | > |   ;
| | > |
| | > | class_<riskcetera::PortfolioDataAccess>("PortfolioAccess")
| | > |   .constructor()
| | > |   .method("read", &riskcetera::PortfolioDataAccess::read)
| | > |   ;
| | > | }
| | > |
| | > | When trying to compile the module I get the following error:
| | > |
| | > |
| | > | /riskcetera/home/aludin/R/x86_64-pc-linux-gnu-library/3.0/Rcpp/include/Rcpp/internal/wrap.h:474:7: error: no viable conversion from 'const riskcetera::Portfolio' to 'SEXP' (aka 'SEXPREC *')
| | > |         SEXP x = object ;
| | >
| | > That is pretty plain:  You need to supply a wrap() converter that tells the
| | > compiler how to turn one of your objects ("Portfolio") into R's standard
| | > type, the SEXP.
| | >
| | > The currently-on-CRAN version of RcpBDT may help you.  It does something
| | > pretty simply with Boost Date_Time, converting dates between the Boost
| | > representation and the Rcpp / R representation.  It uses custom as<>() and
| | > wrap(), and exposes a handful of useful functions too.   [ And do look at the
| | > CRAN version, the R-Forge version is in heavier development which I started
| | > last fall and hope to get back to by the summer. ]
| | >   
| | > Dirk
| | >
| | 
| | 
| | _______________________________________________
| | Rcpp-devel mailing list
| | Rcpp-devel at lists.r-forge.r-project.org
| | https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel
| 
| -- 
| Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com

Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com

Actually I have integrated more complex classes copying Romain's example. 
This included polymorphism (see the answers and discussion around question with subject "Module with vector of a class with inheritance, how to avoid slicing" on this list). I failed to handle very well the case of a template class which might reach the limit of the tool, this was the purpose of my question with subject  "module with a template class" on this list. That question wasn't answered by the way (I see your activity and I confirm this is one over a million)

R.


----- Mail original -----
De: "Dirk Eddelbuettel" <edd at debian.org>
?: "Robin Girard" <robin.girard at mines-paristech.fr>
Cc: "Dirk Eddelbuettel" <edd at debian.org>, "Anwar Ludin" <anwar.ludin at riskcetera.com>, rcpp-devel at lists.r-forge.r-project.org
Envoy?: Lundi 13 Mai 2013 21:38:34
Objet: Re: [Rcpp-devel] using Rcpp modules to expose class

| http://romainfrancois.blog.free.fr/index.php?post/2012/10/25/Rcpp-modules-more-flexible

Oh a good one indeed -- I had forgotten about that aspect (and in fact not
used it yet in a project of mine).

This may indeed work for Anwar, so thanks for the pointer.   

[ That said, I do like explicit code too and the control one has which
explicit converters does come on handy.  Also, his real class may well be
more complicated than the token example from the blog posts so things may or
may not work.  Proof is in the pudding and all that. ]

Dirk

| R.
| 
| ----- Mail original -----
| De: "Dirk Eddelbuettel" <edd at debian.org>
| ?: "Robin Girard" <robin.girard at mines-paristech.fr>
| Cc: "Anwar Ludin" <anwar.ludin at riskcetera.com>, rcpp-devel at lists.r-forge.r-project.org, "Dirk Eddelbuettel" <edd at debian.org>
| Envoy?: Lundi 13 Mai 2013 19:25:09
| Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
| 
|

| | As suggested in the example of Romain's Blog 
| | here http://romainfrancois.blog.free.fr/
| 
| There are dozens of posts regarding Rcpp on his blog.  If you refer to one
| such post, could you show us the relevant (and presumably still valid) URL?  
| 
| Otherwise we just don't know what you refer to.
| 
| | you need to define the class before "exposing" it and then implement it (I think it is also important that using namespace Rcpp  comes after the exposed stuff). 
| | 
| | class Foo ;
| | RCPP_EXPOSED_CLASS(Foo)
| | 
| | using namespace Rcpp ;
| | 
| | class Foo{
| |     public:
| |         enum Bla{ FOO, BAR } ;
| | ... 
| | 
| | 
| | is it what you did ? 
| | I made it work in some cases and I did not have to implement the wrap
| | (which is the whole purpose of module I think). 
| 
| Modules help you with setters/getters of _components of a class you expose_
| in such a declaration.
| 
| What Anwar wants here is different: he wants to pass the whole class as is.
| For which conversion code has to come from somewhere: hence the need for wrap().
| 
| I could of course be misunderstanding the issue too..
| 
| Dirk
| 
| 
| | R.
| | 
| | ----- Mail original -----
| | De: "Anwar Ludin" <anwar.ludin at riskcetera.com>
| | ?: "Dirk Eddelbuettel" <edd at debian.org>
| | Cc: rcpp-devel at lists.r-forge.r-project.org
| | Envoy?: Lundi 13 Mai 2013 16:11:35
| | Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
| | 
| | Hi Dirk,
| | 
| | Thanks for your answer!
| | 
| | So if I understand correctly, the fact that I exposed previously 
| | Portfolio is not enough?
| | I still need to provide wrap the template specialization:
| | 
| |      template <> SEXP wrap( const Portfolio& ) ;
| | 
| | Thanks,
| | 
| | Anwar
| |

| | > | Hello,
| | > |
| | > | I'm trying to expose 2 classes from a Rcpp module:
| | > |
| | > | class Portfolio{
| | > |   private:
| | > |      std::string portfolioId, description;
| | > |   public:
| | > |       Portfolio(std::string portfolioId, std::string description)
| | > |       : portfolioId(portfolioId), description(description) {}
| | > |
| | > |       std::string getPortfolioId() {return portfolioId;} const
| | > |       void setPortfolioId(const std::string&) {this->portfolioId =
| | > | portfolioId;}
| | > |
| | > |       std::string getDescription() {return description;} const
| | > |       void setDescription(const std::string& description){this->description =
| | > | description;}
| | > | };
| | > |
| | > | class PortfolioDataAccess{
| | > |     private:
| | > |     mongo::DBClientConnection c;
| | > |
| | > |     public:
| | > |     PortfolioDataAccess();
| | > |     virtual Portfolio read(std::string portfolioId);
| | > |     virtual void create(std::string portfolioId, std::string description);
| | > |
| | > |   };
| | > |
| | > |
| | > |
| | > |
| | > | RCPP_MODULE(riskceteraPortfolio) {
| | > |   class_<riskcetera::Portfolio>( "Portfolio" )
| | > |   .constructor<std::string, std::string>()
| | >
| | > That works because we can convert "in" from SEXP to std::strings.
| | >
| | > |   .method("id", &riskcetera::Portfolio::getPortfolioId)
| | > |   .method("description", &riskcetera::Portfolio::getDescription)
| | > |   ;
| | > |
| | > | class_<riskcetera::PortfolioDataAccess>("PortfolioAccess")
| | > |   .constructor()
| | > |   .method("read", &riskcetera::PortfolioDataAccess::read)
| | > |   ;
| | > | }
| | > |
| | > | When trying to compile the module I get the following error:
| | > |
| | > |
| | > | /riskcetera/home/aludin/R/x86_64-pc-linux-gnu-library/3.0/Rcpp/include/Rcpp/internal/wrap.h:474:7: error: no viable conversion from 'const riskcetera::Portfolio' to 'SEXP' (aka 'SEXPREC *')
| | > |         SEXP x = object ;
| | >
| | > That is pretty plain:  You need to supply a wrap() converter that tells the
| | > compiler how to turn one of your objects ("Portfolio") into R's standard
| | > type, the SEXP.
| | >
| | > The currently-on-CRAN version of RcpBDT may help you.  It does something
| | > pretty simply with Boost Date_Time, converting dates between the Boost
| | > representation and the Rcpp / R representation.  It uses custom as<>() and
| | > wrap(), and exposes a handful of useful functions too.   [ And do look at the
| | > CRAN version, the R-Forge version is in heavier development which I started
| | > last fall and hope to get back to by the summer. ]
| | >   
| | > Dirk
| | >
| | 
| | 
| | _______________________________________________
| | Rcpp-devel mailing list
| | Rcpp-devel at lists.r-forge.r-project.org
| | https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel
| 
| -- 
| Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com

Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com

Thanks guys! This is exactly what I was looking for...tested it & works :-)

Actually I have integrated more complex classes copying Romain's example.
This included polymorphism (see the answers and discussion around question with subject "Module with vector of a class with inheritance, how to avoid slicing" on this list). I failed to handle very well the case of a template class which might reach the limit of the tool, this was the purpose of my question with subject  "module with a template class" on this list. That question wasn't answered by the way (I see your activity and I confirm this is one over a million)

R.


----- Mail original -----
De: "Dirk Eddelbuettel" <edd at debian.org>
?: "Robin Girard" <robin.girard at mines-paristech.fr>
Cc: "Dirk Eddelbuettel" <edd at debian.org>, "Anwar Ludin" <anwar.ludin at riskcetera.com>, rcpp-devel at lists.r-forge.r-project.org
Envoy?: Lundi 13 Mai 2013 21:38:34
Objet: Re: [Rcpp-devel] using Rcpp modules to expose class


On 13 May 2013 at 21:25, Robin Girard wrote:
| http://romainfrancois.blog.free.fr/index.php?post/2012/10/25/Rcpp-modules-more-flexible

Oh a good one indeed -- I had forgotten about that aspect (and in fact not
used it yet in a project of mine).

This may indeed work for Anwar, so thanks for the pointer.

[ That said, I do like explicit code too and the control one has which
explicit converters does come on handy.  Also, his real class may well be
more complicated than the token example from the blog posts so things may or
may not work.  Proof is in the pudding and all that. ]

Dirk

| R.
|
| ----- Mail original -----
| De: "Dirk Eddelbuettel" <edd at debian.org>
| ?: "Robin Girard" <robin.girard at mines-paristech.fr>
| Cc: "Anwar Ludin" <anwar.ludin at riskcetera.com>, rcpp-devel at lists.r-forge.r-project.org, "Dirk Eddelbuettel" <edd at debian.org>
| Envoy?: Lundi 13 Mai 2013 19:25:09
| Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
|
|
| On 13 May 2013 at 19:05, Robin Girard wrote:
| | As suggested in the example of Romain's Blog
| | here http://romainfrancois.blog.free.fr/
|
| There are dozens of posts regarding Rcpp on his blog.  If you refer to one
| such post, could you show us the relevant (and presumably still valid) URL?
|
| Otherwise we just don't know what you refer to.
|
| | you need to define the class before "exposing" it and then implement it (I think it is also important that using namespace Rcpp  comes after the exposed stuff).
| |
| | class Foo ;
| | RCPP_EXPOSED_CLASS(Foo)
| |
| | using namespace Rcpp ;
| |
| | class Foo{
| |     public:
| |         enum Bla{ FOO, BAR } ;
| | ...
| |
| |
| | is it what you did ?
| | I made it work in some cases and I did not have to implement the wrap
| | (which is the whole purpose of module I think).
|
| Modules help you with setters/getters of _components of a class you expose_
| in such a declaration.
|
| What Anwar wants here is different: he wants to pass the whole class as is.
| For which conversion code has to come from somewhere: hence the need for wrap().
|
| I could of course be misunderstanding the issue too..
|
| Dirk
|
|
| | R.
| |
| | ----- Mail original -----
| | De: "Anwar Ludin" <anwar.ludin at riskcetera.com>
| | ?: "Dirk Eddelbuettel" <edd at debian.org>
| | Cc: rcpp-devel at lists.r-forge.r-project.org
| | Envoy?: Lundi 13 Mai 2013 16:11:35
| | Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
| |
| | Hi Dirk,
| |
| | Thanks for your answer!
| |
| | So if I understand correctly, the fact that I exposed previously
| | Portfolio is not enough?
| | I still need to provide wrap the template specialization:
| |
| |      template <> SEXP wrap( const Portfolio& ) ;
| |
| | Thanks,
| |
| | Anwar
| |
| | On 05/13/2013 03:28 PM, Dirk Eddelbuettel wrote:
| | > On 13 May 2013 at 14:59, Anwar Ludin wrote:
| | > | Hello,
| | > |
| | > | I'm trying to expose 2 classes from a Rcpp module:
| | > |
| | > | class Portfolio{
| | > |   private:
| | > |      std::string portfolioId, description;
| | > |   public:
| | > |       Portfolio(std::string portfolioId, std::string description)
| | > |       : portfolioId(portfolioId), description(description) {}
| | > |
| | > |       std::string getPortfolioId() {return portfolioId;} const
| | > |       void setPortfolioId(const std::string&) {this->portfolioId =
| | > | portfolioId;}
| | > |
| | > |       std::string getDescription() {return description;} const
| | > |       void setDescription(const std::string& description){this->description =
| | > | description;}
| | > | };
| | > |
| | > | class PortfolioDataAccess{
| | > |     private:
| | > |     mongo::DBClientConnection c;
| | > |
| | > |     public:
| | > |     PortfolioDataAccess();
| | > |     virtual Portfolio read(std::string portfolioId);
| | > |     virtual void create(std::string portfolioId, std::string description);
| | > |
| | > |   };
| | > |
| | > |
| | > |
| | > |
| | > | RCPP_MODULE(riskceteraPortfolio) {
| | > |   class_<riskcetera::Portfolio>( "Portfolio" )
| | > |   .constructor<std::string, std::string>()
| | >
| | > That works because we can convert "in" from SEXP to std::strings.
| | >
| | > |   .method("id", &riskcetera::Portfolio::getPortfolioId)
| | > |   .method("description", &riskcetera::Portfolio::getDescription)
| | > |   ;
| | > |
| | > | class_<riskcetera::PortfolioDataAccess>("PortfolioAccess")
| | > |   .constructor()
| | > |   .method("read", &riskcetera::PortfolioDataAccess::read)
| | > |   ;
| | > | }
| | > |
| | > | When trying to compile the module I get the following error:
| | > |
| | > |
| | > | /riskcetera/home/aludin/R/x86_64-pc-linux-gnu-library/3.0/Rcpp/include/Rcpp/internal/wrap.h:474:7: error: no viable conversion from 'const riskcetera::Portfolio' to 'SEXP' (aka 'SEXPREC *')
| | > |         SEXP x = object ;
| | >
| | > That is pretty plain:  You need to supply a wrap() converter that tells the
| | > compiler how to turn one of your objects ("Portfolio") into R's standard
| | > type, the SEXP.
| | >
| | > The currently-on-CRAN version of RcpBDT may help you.  It does something
| | > pretty simply with Boost Date_Time, converting dates between the Boost
| | > representation and the Rcpp / R representation.  It uses custom as<>() and
| | > wrap(), and exposes a handful of useful functions too.   [ And do look at the
| | > CRAN version, the R-Forge version is in heavier development which I started
| | > last fall and hope to get back to by the summer. ]
| | >
| | > Dirk
| | >
| |
| |
| | _______________________________________________
| | Rcpp-devel mailing list
| | Rcpp-devel at lists.r-forge.r-project.org
| | https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel
|
| --
| Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com

| Thanks guys! This is exactly what I was looking for...tested it & works :-)

Nice.

Now it would be even nicer for the rest of us if between you and Robin
someone could volunteer to document this in

   either a new section for the vignette

   or a contributed page / article for gallery.rcpp.org

Dirk

| > Actually I have integrated more complex classes copying Romain's example.
| > This included polymorphism (see the answers and discussion around question with subject "Module with vector of a class with inheritance, how to avoid slicing" on this list). I failed to handle very well the case of a template class which might reach the limit of the tool, this was the purpose of my question with subject  "module with a template class" on this list. That question wasn't answered by the way (I see your activity and I confirm this is one over a million)
| >
| > R.
| >
| >
| > ----- Mail original -----
| > De: "Dirk Eddelbuettel" <edd at debian.org>
| > ?: "Robin Girard" <robin.girard at mines-paristech.fr>
| > Cc: "Dirk Eddelbuettel" <edd at debian.org>, "Anwar Ludin" <anwar.ludin at riskcetera.com>, rcpp-devel at lists.r-forge.r-project.org
| > Envoy?: Lundi 13 Mai 2013 21:38:34
| > Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
| >
| >

| > | http://romainfrancois.blog.free.fr/index.php?post/2012/10/25/Rcpp-modules-more-flexible
| >
| > Oh a good one indeed -- I had forgotten about that aspect (and in fact not
| > used it yet in a project of mine).
| >
| > This may indeed work for Anwar, so thanks for the pointer.
| >
| > [ That said, I do like explicit code too and the control one has which
| > explicit converters does come on handy.  Also, his real class may well be
| > more complicated than the token example from the blog posts so things may or
| > may not work.  Proof is in the pudding and all that. ]
| >
| > Dirk
| >
| > | R.
| > |
| > | ----- Mail original -----
| > | De: "Dirk Eddelbuettel" <edd at debian.org>
| > | ?: "Robin Girard" <robin.girard at mines-paristech.fr>
| > | Cc: "Anwar Ludin" <anwar.ludin at riskcetera.com>, rcpp-devel at lists.r-forge.r-project.org, "Dirk Eddelbuettel" <edd at debian.org>
| > | Envoy?: Lundi 13 Mai 2013 19:25:09
| > | Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
| > |
| > |

| > | | As suggested in the example of Romain's Blog
| > | | here http://romainfrancois.blog.free.fr/
| > |
| > | There are dozens of posts regarding Rcpp on his blog.  If you refer to one
| > | such post, could you show us the relevant (and presumably still valid) URL?
| > |
| > | Otherwise we just don't know what you refer to.
| > |
| > | | you need to define the class before "exposing" it and then implement it (I think it is also important that using namespace Rcpp  comes after the exposed stuff).
| > | |
| > | | class Foo ;
| > | | RCPP_EXPOSED_CLASS(Foo)
| > | |
| > | | using namespace Rcpp ;
| > | |
| > | | class Foo{
| > | |     public:
| > | |         enum Bla{ FOO, BAR } ;
| > | | ...
| > | |
| > | |
| > | | is it what you did ?
| > | | I made it work in some cases and I did not have to implement the wrap
| > | | (which is the whole purpose of module I think).
| > |
| > | Modules help you with setters/getters of _components of a class you expose_
| > | in such a declaration.
| > |
| > | What Anwar wants here is different: he wants to pass the whole class as is.
| > | For which conversion code has to come from somewhere: hence the need for wrap().
| > |
| > | I could of course be misunderstanding the issue too..
| > |
| > | Dirk
| > |
| > |
| > | | R.
| > | |
| > | | ----- Mail original -----
| > | | De: "Anwar Ludin" <anwar.ludin at riskcetera.com>
| > | | ?: "Dirk Eddelbuettel" <edd at debian.org>
| > | | Cc: rcpp-devel at lists.r-forge.r-project.org
| > | | Envoy?: Lundi 13 Mai 2013 16:11:35
| > | | Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
| > | |
| > | | Hi Dirk,
| > | |
| > | | Thanks for your answer!
| > | |
| > | | So if I understand correctly, the fact that I exposed previously
| > | | Portfolio is not enough?
| > | | I still need to provide wrap the template specialization:
| > | |
| > | |      template <> SEXP wrap( const Portfolio& ) ;
| > | |
| > | | Thanks,
| > | |
| > | | Anwar
| > | |

| > | | > | Hello,
| > | | > |
| > | | > | I'm trying to expose 2 classes from a Rcpp module:
| > | | > |
| > | | > | class Portfolio{
| > | | > |   private:
| > | | > |      std::string portfolioId, description;
| > | | > |   public:
| > | | > |       Portfolio(std::string portfolioId, std::string description)
| > | | > |       : portfolioId(portfolioId), description(description) {}
| > | | > |
| > | | > |       std::string getPortfolioId() {return portfolioId;} const
| > | | > |       void setPortfolioId(const std::string&) {this->portfolioId =
| > | | > | portfolioId;}
| > | | > |
| > | | > |       std::string getDescription() {return description;} const
| > | | > |       void setDescription(const std::string& description){this->description =
| > | | > | description;}
| > | | > | };
| > | | > |
| > | | > | class PortfolioDataAccess{
| > | | > |     private:
| > | | > |     mongo::DBClientConnection c;
| > | | > |
| > | | > |     public:
| > | | > |     PortfolioDataAccess();
| > | | > |     virtual Portfolio read(std::string portfolioId);
| > | | > |     virtual void create(std::string portfolioId, std::string description);
| > | | > |
| > | | > |   };
| > | | > |
| > | | > |
| > | | > |
| > | | > |
| > | | > | RCPP_MODULE(riskceteraPortfolio) {
| > | | > |   class_<riskcetera::Portfolio>( "Portfolio" )
| > | | > |   .constructor<std::string, std::string>()
| > | | >
| > | | > That works because we can convert "in" from SEXP to std::strings.
| > | | >
| > | | > |   .method("id", &riskcetera::Portfolio::getPortfolioId)
| > | | > |   .method("description", &riskcetera::Portfolio::getDescription)
| > | | > |   ;
| > | | > |
| > | | > | class_<riskcetera::PortfolioDataAccess>("PortfolioAccess")
| > | | > |   .constructor()
| > | | > |   .method("read", &riskcetera::PortfolioDataAccess::read)
| > | | > |   ;
| > | | > | }
| > | | > |
| > | | > | When trying to compile the module I get the following error:
| > | | > |
| > | | > |
| > | | > | /riskcetera/home/aludin/R/x86_64-pc-linux-gnu-library/3.0/Rcpp/include/Rcpp/internal/wrap.h:474:7: error: no viable conversion from 'const riskcetera::Portfolio' to 'SEXP' (aka 'SEXPREC *')
| > | | > |         SEXP x = object ;
| > | | >
| > | | > That is pretty plain:  You need to supply a wrap() converter that tells the
| > | | > compiler how to turn one of your objects ("Portfolio") into R's standard
| > | | > type, the SEXP.
| > | | >
| > | | > The currently-on-CRAN version of RcpBDT may help you.  It does something
| > | | > pretty simply with Boost Date_Time, converting dates between the Boost
| > | | > representation and the Rcpp / R representation.  It uses custom as<>() and
| > | | > wrap(), and exposes a handful of useful functions too.   [ And do look at the
| > | | > CRAN version, the R-Forge version is in heavier development which I started
| > | | > last fall and hope to get back to by the summer. ]
| > | | >
| > | | > Dirk
| > | | >
| > | |
| > | |
| > | | _______________________________________________
| > | | Rcpp-devel mailing list
| > | | Rcpp-devel at lists.r-forge.r-project.org
| > | | https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel
| > |
| > | --
| > | Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com
| >
| 
|

Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com

I'll try to contribute to the gallery.rcpp.org, after next week. 
R.

----- Mail original -----
De: "Dirk Eddelbuettel" <edd at debian.org>
?: "Anwar Ludin" <anwar.ludin at riskcetera.com>
Cc: "Robin Girard" <robin.girard at mines-paristech.fr>, "Dirk Eddelbuettel" <edd at debian.org>, rcpp-devel at lists.r-forge.r-project.org
Envoy?: Mardi 14 Mai 2013 16:40:37
Objet: Re: [Rcpp-devel] using Rcpp modules to expose class

| Thanks guys! This is exactly what I was looking for...tested it & works :-)

Nice.

Now it would be even nicer for the rest of us if between you and Robin
someone could volunteer to document this in

   either a new section for the vignette

   or a contributed page / article for gallery.rcpp.org

Dirk

| > Actually I have integrated more complex classes copying Romain's example.
| > This included polymorphism (see the answers and discussion around question with subject "Module with vector of a class with inheritance, how to avoid slicing" on this list). I failed to handle very well the case of a template class which might reach the limit of the tool, this was the purpose of my question with subject  "module with a template class" on this list. That question wasn't answered by the way (I see your activity and I confirm this is one over a million)
| >
| > R.
| >
| >
| > ----- Mail original -----
| > De: "Dirk Eddelbuettel" <edd at debian.org>
| > ?: "Robin Girard" <robin.girard at mines-paristech.fr>
| > Cc: "Dirk Eddelbuettel" <edd at debian.org>, "Anwar Ludin" <anwar.ludin at riskcetera.com>, rcpp-devel at lists.r-forge.r-project.org
| > Envoy?: Lundi 13 Mai 2013 21:38:34
| > Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
| >
| >

| > | http://romainfrancois.blog.free.fr/index.php?post/2012/10/25/Rcpp-modules-more-flexible
| >
| > Oh a good one indeed -- I had forgotten about that aspect (and in fact not
| > used it yet in a project of mine).
| >
| > This may indeed work for Anwar, so thanks for the pointer.
| >
| > [ That said, I do like explicit code too and the control one has which
| > explicit converters does come on handy.  Also, his real class may well be
| > more complicated than the token example from the blog posts so things may or
| > may not work.  Proof is in the pudding and all that. ]
| >
| > Dirk
| >
| > | R.
| > |
| > | ----- Mail original -----
| > | De: "Dirk Eddelbuettel" <edd at debian.org>
| > | ?: "Robin Girard" <robin.girard at mines-paristech.fr>
| > | Cc: "Anwar Ludin" <anwar.ludin at riskcetera.com>, rcpp-devel at lists.r-forge.r-project.org, "Dirk Eddelbuettel" <edd at debian.org>
| > | Envoy?: Lundi 13 Mai 2013 19:25:09
| > | Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
| > |
| > |

| > | | As suggested in the example of Romain's Blog
| > | | here http://romainfrancois.blog.free.fr/
| > |
| > | There are dozens of posts regarding Rcpp on his blog.  If you refer to one
| > | such post, could you show us the relevant (and presumably still valid) URL?
| > |
| > | Otherwise we just don't know what you refer to.
| > |
| > | | you need to define the class before "exposing" it and then implement it (I think it is also important that using namespace Rcpp  comes after the exposed stuff).
| > | |
| > | | class Foo ;
| > | | RCPP_EXPOSED_CLASS(Foo)
| > | |
| > | | using namespace Rcpp ;
| > | |
| > | | class Foo{
| > | |     public:
| > | |         enum Bla{ FOO, BAR } ;
| > | | ...
| > | |
| > | |
| > | | is it what you did ?
| > | | I made it work in some cases and I did not have to implement the wrap
| > | | (which is the whole purpose of module I think).
| > |
| > | Modules help you with setters/getters of _components of a class you expose_
| > | in such a declaration.
| > |
| > | What Anwar wants here is different: he wants to pass the whole class as is.
| > | For which conversion code has to come from somewhere: hence the need for wrap().
| > |
| > | I could of course be misunderstanding the issue too..
| > |
| > | Dirk
| > |
| > |
| > | | R.
| > | |
| > | | ----- Mail original -----
| > | | De: "Anwar Ludin" <anwar.ludin at riskcetera.com>
| > | | ?: "Dirk Eddelbuettel" <edd at debian.org>
| > | | Cc: rcpp-devel at lists.r-forge.r-project.org
| > | | Envoy?: Lundi 13 Mai 2013 16:11:35
| > | | Objet: Re: [Rcpp-devel] using Rcpp modules to expose class
| > | |
| > | | Hi Dirk,
| > | |
| > | | Thanks for your answer!
| > | |
| > | | So if I understand correctly, the fact that I exposed previously
| > | | Portfolio is not enough?
| > | | I still need to provide wrap the template specialization:
| > | |
| > | |      template <> SEXP wrap( const Portfolio& ) ;
| > | |
| > | | Thanks,
| > | |
| > | | Anwar
| > | |

| > | | > | Hello,
| > | | > |
| > | | > | I'm trying to expose 2 classes from a Rcpp module:
| > | | > |
| > | | > | class Portfolio{
| > | | > |   private:
| > | | > |      std::string portfolioId, description;
| > | | > |   public:
| > | | > |       Portfolio(std::string portfolioId, std::string description)
| > | | > |       : portfolioId(portfolioId), description(description) {}
| > | | > |
| > | | > |       std::string getPortfolioId() {return portfolioId;} const
| > | | > |       void setPortfolioId(const std::string&) {this->portfolioId =
| > | | > | portfolioId;}
| > | | > |
| > | | > |       std::string getDescription() {return description;} const
| > | | > |       void setDescription(const std::string& description){this->description =
| > | | > | description;}
| > | | > | };
| > | | > |
| > | | > | class PortfolioDataAccess{
| > | | > |     private:
| > | | > |     mongo::DBClientConnection c;
| > | | > |
| > | | > |     public:
| > | | > |     PortfolioDataAccess();
| > | | > |     virtual Portfolio read(std::string portfolioId);
| > | | > |     virtual void create(std::string portfolioId, std::string description);
| > | | > |
| > | | > |   };
| > | | > |
| > | | > |
| > | | > |
| > | | > |
| > | | > | RCPP_MODULE(riskceteraPortfolio) {
| > | | > |   class_<riskcetera::Portfolio>( "Portfolio" )
| > | | > |   .constructor<std::string, std::string>()
| > | | >
| > | | > That works because we can convert "in" from SEXP to std::strings.
| > | | >
| > | | > |   .method("id", &riskcetera::Portfolio::getPortfolioId)
| > | | > |   .method("description", &riskcetera::Portfolio::getDescription)
| > | | > |   ;
| > | | > |
| > | | > | class_<riskcetera::PortfolioDataAccess>("PortfolioAccess")
| > | | > |   .constructor()
| > | | > |   .method("read", &riskcetera::PortfolioDataAccess::read)
| > | | > |   ;
| > | | > | }
| > | | > |
| > | | > | When trying to compile the module I get the following error:
| > | | > |
| > | | > |
| > | | > | /riskcetera/home/aludin/R/x86_64-pc-linux-gnu-library/3.0/Rcpp/include/Rcpp/internal/wrap.h:474:7: error: no viable conversion from 'const riskcetera::Portfolio' to 'SEXP' (aka 'SEXPREC *')
| > | | > |         SEXP x = object ;
| > | | >
| > | | > That is pretty plain:  You need to supply a wrap() converter that tells the
| > | | > compiler how to turn one of your objects ("Portfolio") into R's standard
| > | | > type, the SEXP.
| > | | >
| > | | > The currently-on-CRAN version of RcpBDT may help you.  It does something
| > | | > pretty simply with Boost Date_Time, converting dates between the Boost
| > | | > representation and the Rcpp / R representation.  It uses custom as<>() and
| > | | > wrap(), and exposes a handful of useful functions too.   [ And do look at the
| > | | > CRAN version, the R-Forge version is in heavier development which I started
| > | | > last fall and hope to get back to by the summer. ]
| > | | >
| > | | > Dirk
| > | | >
| > | |
| > | |
| > | | _______________________________________________
| > | | Rcpp-devel mailing list
| > | | Rcpp-devel at lists.r-forge.r-project.org
| > | | https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/rcpp-devel
| > |
| > | --
| > | Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com
| >
| 
|

Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com