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c++ - Vector of structs with const members?

Let's say I have

#include <string>
#include <vector>
using namespace std;

struct Student
{
    const string name;
    int grade;
    Student(const string &name) : name(name) { }
};

How do I, then, keep a vector of students?

int main()
{
    vector<Student> v;

    // error C2582: 'operator =' function is unavailable in 'Student'
    v.push_back(Student("john"));
}

Is there even a way to do this, or must I allocate all the students on the heap, and store a pointer to each of them instead?

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1 Answer

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The simple answer is: you can't. If you have const member variables, then the compiler can't supply a default copy-assignment operator. However, many of the operations that std::vector provides need to make assignments, and therefore require a (public) copy-assignment operator.

Your options are:

  1. Make name non-const.
  2. Write your own copy-assignment operator, and think of a way to deal with "copying" a const member.

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