Question

the error I am given:

no matching function for call to ‘SimpleRecommender::getMovieId(std::string&)’

What is written in my header file(without my other functions):

class MyClass
{

    template<class Iterator>
    int getId(string Name);

};

What is written in my .cc file:

  template<class Iterator>
    double Recommender::generatePrediction(int userid, string Name){
            int movieId=Recommender::getId(Name);
            double avg=0;

            for(Iterator current=ratings.begin();current!=ratings.end();current++){
                    if((*current).movieId==movieId){
                            avg+=(*current).rating;
                            avg/=2.0;
                    }
            }
            return avg;
    }


  template<class Iterator>
    int Recommender::getMovieId(string movieName){
            for(Iterator current=movies.begin();current!=movies.end();current++){
                    if((*current).getName().compare(movieName)==0)
                            return (*current).getId;
                    else{
                            cout<<"ERROR: movie not found"<<endl;
                            exit();
                    }
            }
    };

Note: Ratings is a vector

What would cause this error?

Answer 1

Shouldn’t there be a reference operator in:

 int Recommender::getMovieId(string movieName)

like this?:

int Recommender::getMovieId(string &movieName)

How do you call the function from your code?

Also, if you don’t change the value inside the function, you can consider using const string & instead of string or string &.