Does `name_compare()` calls the default construction or the `operator()` of `class name_compare` in `sort(vs.begin(), vs.end(), name_compare());`?

Does name_compare() calls the default construction or the operator() of class name_compare in sort(vs.begin(), vs.end(), name_compare());?

I think it's the first one.Am i right?

I would be thankful for any hint on this question.

 struct Record {
        string name;
        // ...
    };
    struct name_compare {   // compare Records using "name" as the key
        bool operator()(const Record& a, const Record& b) const
            { return a.name<b.name; }
    };
    void f(vector<Record>& vs)
    {
        sort(vs.begin(), vs.end(), name_compare());
        // ...
    }