std::is_compound

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C++
 
实用工具库
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rel_ops::operator!=
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pair
tuple（C++11）
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类型的支持
基本类型
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Basic types
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基本类型
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is_constructible
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is_move_constructible
is_trivially_move_constructible
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is_assignable
is_trivially_assignable
is_nothrow_assignable		（C++11）
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is_copy_assignable
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is_nothrow_copy_assignable		（C++11）
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is_move_assignable
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is_nothrow_move_assignable		（C++11）
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is_destructible
is_trivially_destructible
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键入特征常数
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Type trait constants
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integral_constant（C++11）
 
Defined in header <type_traits>
template< class T >
struct is_compound;
 （C++11 起）
如果T是一个复合型（即，数组，函数，对象指针，函数指针，成员对象的指针，成员函数指针，参考，阶级，工会，或枚举，包括任何品种合格的变种），提供会员value等于true。对于任何其他类型，value是false.
Original:
If T is a compound type (that is, array, function, object pointer, function pointer, member object pointer, member function pointer, reference, class, union, or enumeration, including any cv-qualified variants), provides the member constant value equal true. For any other type, value is false.
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目录

Inherited from std::integral_constant

Member constants

value
[静态的] </ SPAN></div></div>
true如果 T is a compound type ，false其他方式
Original:
true if T is a compound type , false otherwise
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（公共静态成员常量）

Member functions

operator bool
转换的对象bool，返回value
Original:
converts the object to bool, returns value
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（公共成员函数）

Member types

类型
Original:
Type
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 Definition
value_type bool
type std::integral_constant<bool, value>

</div>

[编辑] 注释

复合类型是由基本类型构成的类型。任何C + +类型可以是基本的或复合.
Original:
Compound types are the types that are constructed from fundamental types. Any C++ type is either fundamental or compound.
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[编辑] 可能的实现

template< class T >
struct is_compound : std::integral_constant<bool, !std::is_fundamental<T>::value> {};

[编辑] 为例

#include <iostream>
#include <type_traits>
 
int main() {
    class cls {};
    std::cout << (std::is_compound<cls>::value
                     ? "T is compound"
                     : "T is not a compound") << '\n';
    std::cout << (std::is_compound<int>::value
                     ? "T is compound"
                     : "T is not a compound") << '\n';
}

Output: 

T is compound
T is not a compound

[编辑] 另请参阅

（C++11）
检查如果一个类型是基本类型
Original:
checks if a type is fundamental type
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（类模板） [edit]
（C++11）
如果一个类型的检查是标量类型
Original:
checks if a type is scalar type
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（类模板） [edit]
（C++11）
如果一个类型的检查对象的类型
Original:
checks if a type is object type
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（类模板） [edit]
（C++11）
检查如果一个类型是数组类型
Original:
checks if a type is an array type
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（类模板） [edit]
来自“http://zh.cppreference.com/mwiki/index.php?title=cpp/types/is_compound&oldid=27550”