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Operator overload << for listing in ostringstream

I have the following macro.

#define STRING_STREAM( data )       \
    ( ( (std::ostringstream&)       \
        ( std::ostringstream( ).seekp( 0, std::ios_base::cur ) << data ) ).str( ) )

I am trying to overload <<to list:

std::ostringstream& operator<<( std::ostringstream& oStrStream, TestEnum& testEnum )
{
    oStrStream << "TestEnum";
    return oStrStream;
}

When I call STRING_STREAM (testEnum), it does not use the overloaded <<. It prints the value of the number of enumerations.

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2 answers
std::ostream& operator<<( std::ostream& oStrStream, const TestEnum testEnum )
{
    oStrStream << "TestEnum";
    return oStrStream;
}
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The problem is that the overloaded <statement expects an argument ..

new ostringstream()

but you give him an argument.

ostringstream()

It is not that corresponds to an overloaded function.

auto_ptr ostringstream . .

#include<sstream>
#include<iostream>
#define STRING_STREAM( data )                                                  \
   ((ostringstream&)( *( auto_ptr<ostringstream>(new ostringstream()) ) << data)).str()

using namespace std;

enum TestEnum { ALPHA, BETA };

ostringstream& operator<<( ostringstream& oss, TestEnum testEnum ){
    oss << "TestEnum";
    return oss;
}
int main(){
    cout << STRING_STREAM( ALPHA ) << endl;
}
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