C++ std::is_nothrow_move_constructible用法及代码示例

<type_traits>头文件中提供了C++ STL的std::is_nothrow_move_constructible模板。 C++ STL的std::is_nothrow_move_constructible模板用于检查给定的类型T T是否为可移动构造，并且众所周知它不会引发任何异常。如果T是可移动构造类型，则返回布尔值true，否则返回false。

头文件：

#include<type_traits>

模板类别：

template <class T>
struct is_nothrow_move_constructible;

用法:

std::is_nothrow_move_constructible<T>::value

参数：模板std::is_nothrow_move_constructible接受单个参数T(Trait类)，以检查T是否为可移动构造类型。

返回值：该模板返回一个布尔变量，如下所示：

True:如果类型T是可移动构造类型。
False:如果类型T不是可移动构造类型。

下面是说明C /C++中的std::is_nothrow_default_constructible模板的程序：

程序：

// C++ program to illustrate 
// std::is_nothrow_move_constructible 
#include <bits/stdc++.h> 
#include <type_traits> 
using namespace std; 
  
// Declare structures 
struct B { 
}; 
  
struct A { 
    A& operator=(A&) = delete; 
}; 
  
struct C { 
    C(C&&) {} 
}; 
  
struct D { 
    D(D&&) = delete; 
}; 
  
// Driver Code 
int main() 
{ 
    cout << boolalpha; 
  
    // Check if int is no throw move 
    // constructible or not 
    cout << "int:"
         << is_nothrow_move_constructible<int>::value 
         << endl; 
  
    // Check if char is no throw move 
    // constructible or not 
    cout << "char:"
         << is_nothrow_move_constructible<char>::value 
         << endl; 
  
    // Check if floar is no throw move 
    // constructible or not 
    cout << "float:"
         << is_nothrow_move_constructible<float>::value 
         << endl; 
  
    // Check if struct A is no throw 
    // move constructible or not 
    cout << "struct A is nothrow move constructible? "
         << is_nothrow_move_constructible<A>::value 
         << endl; 
  
    // Check if struct B is no throw 
    // move constructible or not 
    cout << "struct B is nothrow move constructible? "
         << is_nothrow_move_constructible<B>::value 
         << endl; 
  
    // Check if struct C is no throw 
    // move constructible or not 
    cout << "struct C is nothrow move constructible? "
         << is_nothrow_move_constructible<C>::value 
         << endl; 
  
    // Check if struct D is no throw 
    // move constructible or not 
    cout << "struct D is nothrow move constructible? "
         << is_nothrow_move_constructible<D>::value 
         << endl; 
  
    return 0; 
}

输出：

int:true
char:true
float:true
struct A is nothrow move constructible? true
struct B is nothrow move constructible? true
struct C is nothrow move constructible? false
struct D is nothrow move constructible? false

参考： http://www.cplusplus.com/reference/type_traits/is_nothrow_move_constructible/

相关用法

注：本文由纯净天空筛选整理自bansal_rtk_大神的英文原创作品 std::is_nothrow_move_constructible in C++ with Example。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。