模板方法的专业化 - 我的代码出了什么问题？

Question

这段代码出了什么问题？

class School {
public:
    template<typename T> size_t count() const;
private:
    vector<Boy*> boys;
    vector<Girl*> girls;
};
template<> size_t School::count<Boy>() const {
    return boys.size();
}

我的编译说

error: specialization of ‘size_t School::count() [with T = Boy]’
after instantiation

能否请你帮忙？

PS.这就是我以后要用它的方法:

School s;
size_t c = s.count<Boy>();

Answer 1

你错过了一个分号.

class School {
public:
    template<typename T> size_t count() const;
private:
    vector<Boy*> boys;
    vector<Girl*> girls;
};                           // <-- Missing semi-colon
template<> size_t School::count<Boy>() const {
    return boys.size();
}