std::system_error::operator=

 

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std::system_error

成员函数

system_error::system_error

system_error::operator=

system_error::code

system_error::what

 

system_error& operator=( const system_error& other ) noexcept;		(C++11 起)

以 other 的内容赋值。若赋值后 *this 与 other 均拥有动态类型 std::system_error 则 std::strcmp(what(), other.what()) == 0。

参数

other

-

用以赋值的另一 system_error 对象

返回值

*this

示例

运行此代码

#include <cassert>
#include <cstring>
#include <iostream>
#include <system_error>

void print(const std::system_error& e)
{
    std::cout << "code:    [" << e.code() << "]\n"
                 "message: [" << e.code().message() << "]\n"
                 "what:    [" << e.what() << "]\n\n";
}
 
int main()
{
    std::system_error e1(EDOM, std::generic_category(), "Error info #1");
    print(e1);

    std::system_error e2(EIO, std::system_category(), "Error info #2");
    print(e2);

    e1 = e2;
    assert(std::strcmp(e1.what(), e2.what()) == 0);
    print(e1);
}

可能的输出：

code:    [generic:33]
message: [Numerical argument out of domain]
what:    [Error info #1: Numerical argument out of domain]

code:    [system:5]
message: [Input/output error]
what:    [Error info #2: Input/output error]

code:    [system:5]
message: [Input/output error]
what:    [Error info #2: Input/output error]