std::system_error::operator=

 

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std::system_error

Member functions

system_error::system_error

system_error::operator=

system_error::code

system_error::what

 

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

Assigns the contents with those of other. If *this and other both have dynamic type std::system_error then std::strcmp(what(), other.what()) == 0 after assignment.

Parameters

other

-

another system_error object to assign with

Return value

*this

Example

Run this code

#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);
}

Possible output:

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]