A local function declaration cannot have the same name and type as a function introduced by using declaration. For example: 复制 // functions_in_namespaces2.cpp // C2668 expected namespace B { void f(int); void f(double); } namespace C { void f(int); void f(double); void f(cha...
1. using 声明 using 声明 (using declaration)是将命名空间中单个名字注入到当前作用域的机制,使得在当前作用域下访问另一个作用域下的成员时无需使用限定符:: //...{usingstd::map map<int, std::string> the_map;//ok} map<int, std::string> the_map2;//error using 声明将其它 namespace 的成员...
I'm using the 'using' declaration in C++ to add std::string and std::vector to the local namespace (to save typing unnecessary 'std::'s). using std::string; using std::vector; class Foo { /*...*/ }; What is the scope on this declaration? If I do this in a header, will...
和以前的声明语句一样,这里的声明符也可以包含类型修饰,从而也能由基本数据类型构造出复合类型来。 C++11 中规定了一种新的方法,使用别名声明 (alias declaration) 来定义类型的别名,即使用 using。 在使用的时候,关键字 using 作为别名声明的开始,其后紧跟别名和等号,其作用是把等号左侧的名字规定成等号右侧类型的...
// using_declaration2.cpp#include<stdio.h>classB{public:voidf(char){ printf_s("In B::f()\n"); }voidg(char){ printf_s("In B::g()\n"); } };classC{public:intg(); };classD2:publicB {public:usingB::f;// ok: B is a base of D2// using C::g; // error: C isn...
10.3.3 Theusingdeclaration [namespace.udecl] C++14 标准(ISO/IEC 14882:2014): 7.3.3 Theusingdeclaration [namespace.udecl] C++11 标准(ISO/IEC 14882:2011): 7.3.3 Theusingdeclaration [namespace.udecl] C++03 标准(ISO/IEC 14882:2003): ...
The using declaration in C++ 嗷嗷按,用C++这么多年,还真的第一次注意到有这个东西,具体所有细节还没整理出来。 先用个例子说明一下大概 classAA{ public: inti; intj; }; classBB:privateAA{ public: usingAA::i; }; intmain(){ BB b; b.i=1;//OK, no problem...
error: using-declaration for non-member at class scope using std::cout; When the .h file that containsusing std::coutis used elsewhere it works, but when added to this project it gives this error. What can be the problem? usingstd::cout;usingstd::endl;classTextManager:public...
To export the data automatically from the DLL, use this declaration: __declspec(dllexport) ULONG ulDataInDLL; If you choose to use__declspec(dllimport)along with a .DEF file, you should change the .DEF file to use DATA in place of CONSTANT to reduce the likelihood that incorrect coding ...
To export the data automatically from the DLL, use this declaration: __declspec(dllexport) ULONG ulDataInDLL; Using a .DEF File If you choose to use__declspec(dllimport)along with a .DEF file, you should change the .DEF file to use DATA in place of CONSTANT to reduce the likelihood th...