.. _program_listing_file_src_rdf4cpp_namespaces_RDF.cpp:

Program Listing for File RDF.cpp
================================

|exhale_lsh| :ref:`Return to documentation for file <file_src_rdf4cpp_namespaces_RDF.cpp>` (``src/rdf4cpp/namespaces/RDF.cpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   #include "RDF.hpp"
   
   #include <charconv>
   
   namespace rdf4cpp::namespaces {
   
   RDF::RDF(storage::DynNodeStoragePtr node_storage) : ClosedNamespace{prefix, suffixes, node_storage} {}
   
   IRI RDF::operator+(std::string_view suffix) const {
       if (suffix.starts_with('_')) {
           size_t id;
           auto from_chars_result = std::from_chars(suffix.data() + 1, suffix.data() + suffix.size(), id);
           if (from_chars_result.ec == std::errc() and from_chars_result.ptr == suffix.data() + suffix.size()) {
               std::string normalized_suffix = std::string{"_"} + std::to_string(id);
               return Namespace::operator+(normalized_suffix); // add rdf:_<id> which is also a valid member of this namespace
           } else {
               std::ostringstream oss;
               oss << "Resource " << suffix << " does not exist within the vocabulary " << namespace_iri_ << '.';
               throw std::runtime_error{oss.str()};
           }
       }
       return ClosedNamespace::operator+(suffix);
   }
   
   }  // namespace rdf4cpp::namespaces