std::is_bind_expression

 

C++

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日期和时间

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initializer_list （C++11）

bitset

hash （C++11）

关系运算符 Original: Relational operators The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

rel_ops::operator!= rel_ops::operator> rel_ops::operator<= rel_ops::operator>=

双和元组 Original: Pairs and tuples The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

pair

tuple （C++11）

piecewise_construct_t （C++11）

piecewise_construct （C++11）

掉期，远期和移动 Original: Swap, forward and move The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

swap

forward （C++11）

move （C++11）

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declval （C++11）

 

函数对象

功能包装 Original: Function wrappers The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
function （C++11）
mem_fn （C++11）
bad_function_call （C++11）
绑定 Original: Bind The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
bind （C++11）
is_bind_expression （C++11）
is_placeholder （C++11）
_1, _2, _3, ... （C++11）
参考包装 Original: Reference wrappers The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
reference_wrapper （C++11）
ref cref （C++11） （C++11）
操作包装 Original: Operator wrappers The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
plus minus negate multiplies divides modulus logical_and logical_or logical_not	equal_to not_equal_to greater less greater_equal less_equal bit_and bit_or bit_xor
否定词 Original: Negators The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
unary_negate binary_negate	not1 not2
已过时粘合剂和适配器 Original: Deprecated binders and adaptors The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
unary_function （过时了）
binary_function （过时了）
ptr_fun （过时了）
pointer_to_unary_function （过时了）
pointer_to_binary_function （过时了）
mem_fun （过时了）
mem_fun_t mem_fun1_t const_mem_fun_t const_mem_fun1_t （过时了） （过时了） （过时了） （过时了）
mem_fun_ref （过时了）
mem_fun_ref_t mem_fun1_ref_t const_mem_fun_ref_t const_mem_fun1_ref_t （过时了） （过时了） （过时了） （过时了）
binder1st binder2nd （过时了） （过时了）
bind1st bind2nd （过时了） （过时了）

 

Defined in header <functional>
template< class T > struct is_bind_expression;		（C++11 起）

T是std::bind的调用所产生的类型，这个模板提供成员value等于true。对于任何其他类型，value是false.

Original:

If T is the type produced by a call to std::bind, this template provides the member constant value equal true. For any other type, value is false.

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这个模板可以专门为一个用户定义的类型，应被视为std::bind，如果它是一个绑定的子表达式的类型：当绑定生成的函数对象被调用时，这种类型的绑定参数的函数将被调用对象，将所有未绑定的参数传递给绑定生成的对象.....

Original:

This template may be specialized for a user-defined type which should be treated by std::bind as if it was the type of a bind subexpression: when a bind-generated function object is invoked, a bound argument of this type will be invoked as a function object and will be given all the unbound arguments passed to the bind-generated object.

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Inherited from std::integral_constant

Member constants

value [静态的] </ SPAN></div></div>	true如果 T is a function object generated by std::bind，false其他方式 Original: true if T is a function object generated by std::bind, false otherwise The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. （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 The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. （公共成员函数）

Member types

类型 Original: Type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.	Definition
value_type	bool
type	std::integral_constant<bool, value>

</div>

为例

#include <iostream>
#include <type_traits>
#include <functional>
 
struct MyBind {
    typedef int result_type;
    int operator()(int a, int b) const { return a + b; }
};
 
namespace std {
    template<>
    struct is_bind_expression<MyBind> : public true_type {};
}
 
int f(int n1, int n2)
{
    return n1+n2;
}
 
int main()
{
    // as if bind(f, bind(MyBind::operator(), _1, _2), 2)
    auto b = std::bind(f, MyBind(), 2);
 
    std::cout << "Adding 2 to the sum of 10 and 11 gives " << b(10, 11) << '\n';
}

Output:

Adding 2 to the sum of 10 and 11 gives 23

另请参阅

bind （C++11）	绑定一个或多个参数的函数对象 Original: binds one or more arguments to a function object The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. （函数模板）