Question

#include <iostream>
#include <string>

class c1
{
 public:
  static std::string m1;
  static unsigned int m2;
};

//std::string c1::m1 = std::string;
unsigned int c1::m2 = 0;

void main()
{
 c1 a;
 //std::cout<<a.m1<<std::endl;
 std::cout<<a.m2<<std::endl;
}

In this program enabling the two remarked lines causes an error on the first.

error C2275: ‘std::string’ : illegal use of this type as an expression

What am I doing wrong?

Answer 1

The error says it all, you are using the type std::string as the value to be assigned.

To fix this you can do:

std::string c1::m1 = std::string();
                                ^^

or just

std::string c1::m1;