移動構造函數抱怨「非類類型」

Question

所有的，我玩弄瞭解r值，l值和scott meyers稱之爲「通用引用」。我在設置示例時遇到了一些問題，如下所示。誰能提供一些指導？

#include <cstdio> 

namespace who_needs_namespaces { 

class SomeSillyClass { 
    public: 
    SomeSillyClass() { 
     printf("Default constructed.\n"); 
    } 
    SomeSillyClass(const SomeSillyClass& rhs) { 
     printf("L-Value constructed.\n"); 
    } 
    SomeSillyClass(SomeSillyClass&& rhs) { 
     printf("R-Value Constructed.\n"); 
    } 

    void doStuff() const { 
     printf("doing...\n"); 
    } 
}; 

template<typename T> 
class HolderByValue { 
public: 
    HolderByValue() = delete; 
    HolderByValue(T toHold) : m_mine(toHold) 
    { }; 

private: 
    T m_mine; 
}; 

template<typename T> 
class HolderByRef { 
public: 
    HolderByRef() = delete; 
    HolderByRef(T&& toHold) : m_mine(toHold) 
    { }; 

private: 
    T m_mine; 
}; 

} 

using namespace who_needs_namespaces; 

int main() { 
    //Check our silly class. 
    SomeSillyClass defaultCtr; 
    defaultCtr.doStuff(); 
    SomeSillyClass copyCtr(defaultCtr); 
    copyCtr.doStuff(); 
    SomeSillyClass moveCtr(SomeSillyClass); 
    moveCtr.doStuff(); 

    //Check our HolderByValue 
    //HolderByValue<SomeSillyClass> holder(defaultCtr); 
    HolderByValue<SomeSillyClass &> holder(defaultCtr); 

} 

---

main.cpp: In function 'int main()': 
main.cpp:59:13: error: request for member 'doStuff' in 'moveCtr', which is of non-class type 'who_needs_namespaces::SomeSillyClass(who_needs_namespaces::SomeSillyClass)' 

Answer 1

我認爲你犧牲品什麼斯科特邁爾斯調用C++的最棘手的解析。 https://en.wikipedia.org/wiki/Most_vexing_parse