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class operator overloading error

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  • J jericho63

    This post is deleted!

    Pl45m4P Offline
    Pl45m4P Offline
    Pl45m4
    wrote on last edited by Pl45m4
    #5

    @jericho63 said in class operator overloading error:

    erreur : type 'const QString' does not provide a call operator

    This says it all.
    In the example the members are private and therefore access functions are used to retrieve the value, which you don't have.
    Your nom and prenom are just (public) strings in your class, while key.name(), as used in the example, is the get function to return the private class member.
    Make your members private and write get functions or remove the (), so that it's not a function call anymore.


    If debugging is the process of removing software bugs, then programming must be the process of putting them in.

    ~E. W. Dijkstra

    J 1 Reply Last reply
    2
    • Pl45m4P Pl45m4

      @jericho63 said in class operator overloading error:

      erreur : type 'const QString' does not provide a call operator

      This says it all.
      In the example the members are private and therefore access functions are used to retrieve the value, which you don't have.
      Your nom and prenom are just (public) strings in your class, while key.name(), as used in the example, is the get function to return the private class member.
      Make your members private and write get functions or remove the (), so that it's not a function call anymore.

      J Offline
      J Offline
      jericho63
      wrote on last edited by
      #6

      thank , this is a long time i have no made code.
      I remember it now.
      i have also this error

      'qHashMulti' was not declared in this scope
      

      this error mean, i need an .h file, but i find a QMultiHash only.

      I don't understand

      Pl45m4P 1 Reply Last reply
      0
      • J jericho63

        thank , this is a long time i have no made code.
        I remember it now.
        i have also this error

        'qHashMulti' was not declared in this scope
        

        this error mean, i need an .h file, but i find a QMultiHash only.

        I don't understand

        Pl45m4P Offline
        Pl45m4P Offline
        Pl45m4
        wrote on last edited by Pl45m4
        #7

        @jericho63

        Do you use Qt6 or Qt5?

        Found out that the qHashMulti expression is only available in Qt6.0.0 and later.

        • https://doc.qt.io/qt-6/qhash.html#qHashMulti

        I guess you have to pick another qHash function from one of those, if you use Qt5:

        • https://doc.qt.io/qt-5/qhash.html#related-non-members

        If debugging is the process of removing software bugs, then programming must be the process of putting them in.

        ~E. W. Dijkstra

        J 1 Reply Last reply
        1
        • Pl45m4P Pl45m4

          @jericho63

          Do you use Qt6 or Qt5?

          Found out that the qHashMulti expression is only available in Qt6.0.0 and later.

          • https://doc.qt.io/qt-6/qhash.html#qHashMulti

          I guess you have to pick another qHash function from one of those, if you use Qt5:

          • https://doc.qt.io/qt-5/qhash.html#related-non-members
          J Offline
          J Offline
          jericho63
          wrote on last edited by
          #8

          @Pl45m4

          i use qt6.6

          Pl45m4P 1 Reply Last reply
          0
          • J jericho63

            @Pl45m4

            i use qt6.6

            Pl45m4P Offline
            Pl45m4P Offline
            Pl45m4
            wrote on last edited by
            #9

            @jericho63

            Then including QHash or QMultiHash should fix this.


            If debugging is the process of removing software bugs, then programming must be the process of putting them in.

            ~E. W. Dijkstra

            J 1 Reply Last reply
            1
            • Pl45m4P Pl45m4

              @jericho63

              Then including QHash or QMultiHash should fix this.

              J Offline
              J Offline
              jericho63
              wrote on last edited by jericho63
              #10

              @Pl45m4
              hello

              ok, no morre error at the class side declaration but another one yet when i insert objet un Qset

                          cSoldierd temp;
                          temp.asn = query3.value(5).toString();
                          temp.nom = query3.value(1).toString();
                          temp.prenom = query3.value(2).toString();
                          temp.initiale = query3.value(3).toString();
                          temp.initiale2 = query3.value(4).toString();
                          temp.suffixe = query3.value(6).toString();
                          temp.unit = query3.value(7).toString();
                          temp.id =  query3.value(0).toString();
                          temp.sunit = query3.value(8).toString();
                          temp.nb = 1;
                          scSoldierd.insert(temp);
              
              C:\Users\john MIller\Documents\Gest_base\mainwindow.cpp:243: erreur : static assertion failed: The key type must have a qHash overload or a std::hash specialization
              
              
              jsulmJ 1 Reply Last reply
              0
              • J jericho63

                @Pl45m4
                hello

                ok, no morre error at the class side declaration but another one yet when i insert objet un Qset

                            cSoldierd temp;
                            temp.asn = query3.value(5).toString();
                            temp.nom = query3.value(1).toString();
                            temp.prenom = query3.value(2).toString();
                            temp.initiale = query3.value(3).toString();
                            temp.initiale2 = query3.value(4).toString();
                            temp.suffixe = query3.value(6).toString();
                            temp.unit = query3.value(7).toString();
                            temp.id =  query3.value(0).toString();
                            temp.sunit = query3.value(8).toString();
                            temp.nb = 1;
                            scSoldierd.insert(temp);
                
                C:\Users\john MIller\Documents\Gest_base\mainwindow.cpp:243: erreur : static assertion failed: The key type must have a qHash overload or a std::hash specialization
                
                
                jsulmJ Offline
                jsulmJ Offline
                jsulm
                Lifetime Qt Champion
                wrote on last edited by
                #11

                @jericho63 So, is there a qHash overload for the key type?

                https://forum.qt.io/topic/113070/qt-code-of-conduct

                J 1 Reply Last reply
                0
                • jsulmJ jsulm

                  @jericho63 So, is there a qHash overload for the key type?

                  J Offline
                  J Offline
                  jericho63
                  wrote on last edited by
                  #12

                  @jsulm

                  I suppose not, but how i do this?
                  I have reread the doc, i haven't find an example.

                  class cSoldierd
                      {
                      public:
                          friend int  operator < ( const cSoldierd &s1, const cSoldierd &s2 )
                          {
                              return ( (s1.nom+"|"+s1.prenom+"|"+s1.initiale+"|"+s1.initiale2+"|"+s1.suffixe) < (s2.nom+"|"+s2.prenom+"|"+s2.initiale+"|"+s2.initiale2+"|"+s2.suffixe) );
                          };
                          friend bool operator == (  const cSoldierd &s1 , const cSoldierd &s2   )
                          {
                              return ((s2.nom+"|"+s2.prenom+"|"+s2.initiale+"|"+s2.initiale2+"|"+s2.suffixe) == (s1.nom+"|"+s1.prenom+"|"+s1.initiale+"|"+s1.initiale2+"|"+s1.suffixe));
                          };
                      
                          inline size_t qHash(const cSoldierd &key, size_t seed)
                          {
                              return qHashMulti (seed, key.nom,key.prenom,key.initiale,key.initiale2,key.suffixe);
                      
                          }
                          
                      
                          QString id;
                          QString nom;
                          QString prenom;
                          QString initiale;
                          QString initiale2;
                          QString suffixe;
                          QString unit;
                          QString sunit;
                          QString asn;
                      
                          QString ligne()
                          {
                              return id+"-"+nom+"-"+prenom+"-"+initiale+"-"+initiale2+"-"+suffixe+"-"+unit+"-"+sunit+"-"+asn;
                      
                          }
                          int nb;
                      
                      };
                  
                  jsulmJ 1 Reply Last reply
                  0
                  • J jericho63

                    @jsulm

                    I suppose not, but how i do this?
                    I have reread the doc, i haven't find an example.

                    class cSoldierd
                        {
                        public:
                            friend int  operator < ( const cSoldierd &s1, const cSoldierd &s2 )
                            {
                                return ( (s1.nom+"|"+s1.prenom+"|"+s1.initiale+"|"+s1.initiale2+"|"+s1.suffixe) < (s2.nom+"|"+s2.prenom+"|"+s2.initiale+"|"+s2.initiale2+"|"+s2.suffixe) );
                            };
                            friend bool operator == (  const cSoldierd &s1 , const cSoldierd &s2   )
                            {
                                return ((s2.nom+"|"+s2.prenom+"|"+s2.initiale+"|"+s2.initiale2+"|"+s2.suffixe) == (s1.nom+"|"+s1.prenom+"|"+s1.initiale+"|"+s1.initiale2+"|"+s1.suffixe));
                            };
                        
                            inline size_t qHash(const cSoldierd &key, size_t seed)
                            {
                                return qHashMulti (seed, key.nom,key.prenom,key.initiale,key.initiale2,key.suffixe);
                        
                            }
                            
                        
                            QString id;
                            QString nom;
                            QString prenom;
                            QString initiale;
                            QString initiale2;
                            QString suffixe;
                            QString unit;
                            QString sunit;
                            QString asn;
                        
                            QString ligne()
                            {
                                return id+"-"+nom+"-"+prenom+"-"+initiale+"-"+initiale2+"-"+suffixe+"-"+unit+"-"+sunit+"-"+asn;
                        
                            }
                            int nb;
                        
                        };
                    
                    jsulmJ Offline
                    jsulmJ Offline
                    jsulm
                    Lifetime Qt Champion
                    wrote on last edited by
                    #13

                    @jericho63 said in class operator overloading error:

                    but how i do this?

                    By defining size_t qHash(const cSoldierd &key, size_t seed) outside of the class, not as class member. Same for the other operators in your code (there is also no need to use keyword "friend" for methods).

                    https://forum.qt.io/topic/113070/qt-code-of-conduct

                    J 1 Reply Last reply
                    2
                    • jsulmJ jsulm

                      @jericho63 said in class operator overloading error:

                      but how i do this?

                      By defining size_t qHash(const cSoldierd &key, size_t seed) outside of the class, not as class member. Same for the other operators in your code (there is also no need to use keyword "friend" for methods).

                      J Offline
                      J Offline
                      jericho63
                      wrote on last edited by
                      #14

                      @jsulm

                      ok, i have deplace size_t qHash(const cSoldierd &key, size_t seed) and the operator outside the class like thos :

                      class cSoldierd
                      {
                      public:
                      
                      
                      
                          QString id;
                          QString nom;
                          QString prenom;
                          QString initiale;
                          QString initiale2;
                          QString suffixe;
                          QString unit;
                          QString sunit;
                          QString asn;
                      
                          QString ligne()
                          {
                              return id+"-"+nom+"-"+prenom+"-"+initiale+"-"+initiale2+"-"+suffixe+"-"+unit+"-"+sunit+"-"+asn;
                      
                          }
                          int nb;
                      
                      };
                      inline size_t qHash(const cSoldierd &key, size_t seed)
                      {
                          return qHashMulti (seed, key.nom,key.prenom,key.initiale,key.initiale2,key.suffixe);
                      
                      }
                      int  operator < ( const cSoldierd &s1, const cSoldierd &s2 )
                      {
                          return ( (s1.nom+"|"+s1.prenom+"|"+s1.initiale+"|"+s1.initiale2+"|"+s1.suffixe) < (s2.nom+"|"+s2.prenom+"|"+s2.initiale+"|"+s2.initiale2+"|"+s2.suffixe) );
                      };
                      bool operator == (  const cSoldierd &s1 , const cSoldierd &s2   )
                      {
                          return ((s2.nom+"|"+s2.prenom+"|"+s2.initiale+"|"+s2.initiale2+"|"+s2.suffixe) == (s1.nom+"|"+s1.prenom+"|"+s1.initiale+"|"+s1.initiale2+"|"+s1.suffixe));
                      };
                      

                      but now i have more errors:

                      :-1: erreur : CMakeFiles/Gest_base.dir/main.cpp.obj: in function `bool std::__constant_string_p<char>(char const*)':
                      
                      \mainwindow.h:52: erreur : multiple definition of `operator<(cSoldierd const&, cSoldierd const&)'; CMakeFiles/Gest_base.dir/Gest_base_autogen/mocs_compilation.cpp.obj:mainwindow.h:52: first defined here
                      

                      i don't understand the second error, i have only one definition for each operator

                      Christian EhrlicherC J 2 Replies Last reply
                      0
                      • J jericho63

                        @jsulm

                        ok, i have deplace size_t qHash(const cSoldierd &key, size_t seed) and the operator outside the class like thos :

                        class cSoldierd
                        {
                        public:
                        
                        
                        
                            QString id;
                            QString nom;
                            QString prenom;
                            QString initiale;
                            QString initiale2;
                            QString suffixe;
                            QString unit;
                            QString sunit;
                            QString asn;
                        
                            QString ligne()
                            {
                                return id+"-"+nom+"-"+prenom+"-"+initiale+"-"+initiale2+"-"+suffixe+"-"+unit+"-"+sunit+"-"+asn;
                        
                            }
                            int nb;
                        
                        };
                        inline size_t qHash(const cSoldierd &key, size_t seed)
                        {
                            return qHashMulti (seed, key.nom,key.prenom,key.initiale,key.initiale2,key.suffixe);
                        
                        }
                        int  operator < ( const cSoldierd &s1, const cSoldierd &s2 )
                        {
                            return ( (s1.nom+"|"+s1.prenom+"|"+s1.initiale+"|"+s1.initiale2+"|"+s1.suffixe) < (s2.nom+"|"+s2.prenom+"|"+s2.initiale+"|"+s2.initiale2+"|"+s2.suffixe) );
                        };
                        bool operator == (  const cSoldierd &s1 , const cSoldierd &s2   )
                        {
                            return ((s2.nom+"|"+s2.prenom+"|"+s2.initiale+"|"+s2.initiale2+"|"+s2.suffixe) == (s1.nom+"|"+s1.prenom+"|"+s1.initiale+"|"+s1.initiale2+"|"+s1.suffixe));
                        };
                        

                        but now i have more errors:

                        :-1: erreur : CMakeFiles/Gest_base.dir/main.cpp.obj: in function `bool std::__constant_string_p<char>(char const*)':
                        
                        \mainwindow.h:52: erreur : multiple definition of `operator<(cSoldierd const&, cSoldierd const&)'; CMakeFiles/Gest_base.dir/Gest_base_autogen/mocs_compilation.cpp.obj:mainwindow.h:52: first defined here
                        

                        i don't understand the second error, i have only one definition for each operator

                        Christian EhrlicherC Online
                        Christian EhrlicherC Online
                        Christian Ehrlicher
                        Lifetime Qt Champion
                        wrote on last edited by
                        #15

                        You must define them inline

                        Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                        Visit the Qt Academy at https://academy.qt.io/catalog

                        1 Reply Last reply
                        3
                        • J jericho63

                          @jsulm

                          ok, i have deplace size_t qHash(const cSoldierd &key, size_t seed) and the operator outside the class like thos :

                          class cSoldierd
                          {
                          public:
                          
                          
                          
                              QString id;
                              QString nom;
                              QString prenom;
                              QString initiale;
                              QString initiale2;
                              QString suffixe;
                              QString unit;
                              QString sunit;
                              QString asn;
                          
                              QString ligne()
                              {
                                  return id+"-"+nom+"-"+prenom+"-"+initiale+"-"+initiale2+"-"+suffixe+"-"+unit+"-"+sunit+"-"+asn;
                          
                              }
                              int nb;
                          
                          };
                          inline size_t qHash(const cSoldierd &key, size_t seed)
                          {
                              return qHashMulti (seed, key.nom,key.prenom,key.initiale,key.initiale2,key.suffixe);
                          
                          }
                          int  operator < ( const cSoldierd &s1, const cSoldierd &s2 )
                          {
                              return ( (s1.nom+"|"+s1.prenom+"|"+s1.initiale+"|"+s1.initiale2+"|"+s1.suffixe) < (s2.nom+"|"+s2.prenom+"|"+s2.initiale+"|"+s2.initiale2+"|"+s2.suffixe) );
                          };
                          bool operator == (  const cSoldierd &s1 , const cSoldierd &s2   )
                          {
                              return ((s2.nom+"|"+s2.prenom+"|"+s2.initiale+"|"+s2.initiale2+"|"+s2.suffixe) == (s1.nom+"|"+s1.prenom+"|"+s1.initiale+"|"+s1.initiale2+"|"+s1.suffixe));
                          };
                          

                          but now i have more errors:

                          :-1: erreur : CMakeFiles/Gest_base.dir/main.cpp.obj: in function `bool std::__constant_string_p<char>(char const*)':
                          
                          \mainwindow.h:52: erreur : multiple definition of `operator<(cSoldierd const&, cSoldierd const&)'; CMakeFiles/Gest_base.dir/Gest_base_autogen/mocs_compilation.cpp.obj:mainwindow.h:52: first defined here
                          

                          i don't understand the second error, i have only one definition for each operator

                          J Offline
                          J Offline
                          jericho63
                          wrote on last edited by
                          #16

                          @jericho63

                          that's work!
                          Thank you
                          The operator overload no longer need to be define in a class now?

                          1 Reply Last reply
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