A Magic Spell: Using auto and decltype in C++11 to Declare Objects Without Spelling Out Their TypesDanny Kalev
// and type of y is same as return type of fun2() decltype(fun1())x; decltype(fun2())y; cout<<typeid(x).name()<<endl; cout<<typeid(y).name()<<endl; return0; } 输出 i c 下面再举一个例子来演示decltype的使用, CPP实现 // C++ program to demonstrate use of decltype #include...
In this tutorial, we will be discussing a program to understand Type interference in C++ (auto and decltype). In the case of auto keyword, the type of the variable is defined from the type of its initializer. Further, with decltype, it lets you extract the type of variable from the ...
decltype(auto)//可以工作，authAndAccess(Container&c,Indexi)//但是还需要{//改良authenticateUser();...
decltype(ci) x = 0;// x has type const int decltype(cj) y = x;// y has type const int & and is bound to x decltype(cj) z;// error: z is a reference and must be initialized. 当表达式不是变量,而是可作为左值的对象时,那么decltype返回的时指向该对象类型的应用。
inta=3,b=4;decltype(a)c=a;// <=> int c = a; c 是int 型decltype(a=b)d=a;// <=>...
decltype(r+0) b;//ok: addition yields anint; b is an (uninitialized)intdecltype(*p) c;//error: c isint&andmust be initialized Here r is a reference, so decltype(r) is a reference type. If we want the type to which r refers, we can use r in an expression, such as r+0, ...
This is way better for the caller, and the template code loses nothing in readability--if anything, it's easier to understand! The joy of decltype and the new return value syntax Now you might be saying here--okay, that's great, but what if I wanted to *return* the value that this...
1.1 Changes from N1607 Changes to the previous revisions primarily reflect the EWG discussions and results of the straw votes that took place in the Kona and Sydney meetings. In addition, we suggest a change to the rules of decltype for certain built-in operators, and for expressions that ...
TODO: 继续介绍 `auto &`, `auto const &`, `auto &&`, `decltype(auto)`, `auto *`, `auto const *` TODO1 change: 0 additions & 1 deletion 1 docs/hello_world.md Original file line numberDiff line numberDiff line change @@ -134,4 +134,3 @@ int main() ``` > {{ icon.tip...