class operator overloading error

[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

[jericho63]

@Pl45m4

i use qt6.6

[Pl45m4]

@jericho63

Then including QHash or QMultiHash should fix this.

[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

[jsulm]

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

[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;
    
    };

[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).

[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 Ehrlicher]

You must define them inline

[jericho63]

@jericho63

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