Overloading QMap << operator

[The 11th plague of Egypt]

I don't remember very well how to overload operators in a template, so I humbly hope somebody can help me with this.

I'd like to do something like this

Contact contact("Name", "Surname");
QMap<QString, Contact> map;
map.insert("first", contact);
qDebug() << map;

Contact contact("Name", "Surname");
QMap<QString, Contact> map;
map.insert("first", contact);
qDebug() << map;

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and have an output like this

first: Name Surname

first: Name Surname

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This is a just a basic example to help me understand templates, I know there are simpler ways, like a for loop.
BTW is it possible to have a different overloading of << for QMap<QString, Contact> and QMap<Contact, QString> ?

[high_flyer]

I don't remember very well how to overload operators in a template

Ok.
So post the overloading for a regular class then, and we'll go from there.

[The 11th plague of Egypt]

Hum, I know that the best way to overload the << operator is using an external function.

ostream& operator<<(ostream &os, const myClass &mc)
{
    return os << myClass.whatever;
}

ostream& operator<<(ostream &os, const myClass &mc)
{
    return os << myClass.whatever;
}

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And declare that function as a friend of the class

Class myClass
{
    friend ostream& operator<<(ostream &os, const myClass &mc);
    //etc
};

Class myClass
{
    friend ostream& operator<<(ostream &os, const myClass &mc);
    //etc
};

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I know templates are a little different though, and I don't know if I can use qDebug() just like an STL ostream.

[wysota]

Providing support for the QDebug stream operator