const_generic_proxy.h

Go to the documentation of this file.

// const_generic_proxy.h: Rcpp R/C++ interface class library --
//
// Copyright (C) 2013 - 2018 Romain Francois
//
// This file is part of Rcpp.
//
// Rcpp is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 2 of the License, or
// (at your option) any later version.
//
// Rcpp is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Rcpp.  If not, see <http://www.gnu.org/licenses/>.
 
#ifndef Rcpp__vector__const_generic_proxy_h
#define Rcpp__vector__const_generic_proxy_h
 
namespace Rcpp{
namespace internal{
 
    template <int RTYPE, template <class> class StoragePolicy>
        class const_generic_proxy : public GenericProxy< const_generic_proxy<RTYPE, StoragePolicy> > {
                public:
                        typedef typename ::Rcpp::Vector<RTYPE, StoragePolicy> VECTOR ;
 
                        const_generic_proxy(): parent(0), index(-1){}
 
                        const_generic_proxy( const const_generic_proxy& other ) :
                                parent(other.parent), index(other.index){} ;
 
                        const_generic_proxy( const VECTOR& v, R_xlen_t i ) : parent(&v), index(i){} ;
 
                        operator SEXP() const {
                            return get() ;
                        }
 
                        template <typename U> operator U() const {
                                return ::Rcpp::as<U>(get()) ;
                        }
 
                        // helping the compiler (not sure why it can't help itself)
                        operator bool() const { return ::Rcpp::as<bool>(get()) ; }
                        operator int() const { return ::Rcpp::as<int>(get()) ; }
 
                        inline void move(R_xlen_t n) { index += n ; }
 
                        const VECTOR* parent;
                        R_xlen_t index ;
 
                private:
 
                    inline SEXP get() const {
                            return VECTOR_ELT(*parent, index );
                        }
 
        }  ;
 
}
}
 
#endif