using static member variable of a class inside a method of this same class

Question

if I have a static member variable of a class A declared in the file Af.h and I want to use this variable inside a method "met" of this same class inside the file Af.cpp, how do I proceed? here is my files

Af.h

class A
{
  public:
    static std::vector <int> vec;
    void met();
//....
};

Af.cpp

//...
void A::met()
{
// I will use here some int variable i
vec.push_back(i);
//...
}

Unfortunately,this code provides the following compiling error:

undefined reference to A::vec

That's not a compiler error. That's a linker error. You're missing the definition of `vec`. — Kerrek SB, Jun 30 '15 at 08:11
Duplicates: http://stackoverflow.com/q/1563897, http://stackoverflow.com/q/195207 — Kerrek SB, Jun 30 '15 at 08:12

score 0 · Accepted Answer · answered Jun 30 '15 at 08:12

0

You need to define it in Af.cpp:

std::vector<int> A::vec;

answered Jun 30 '15 at 08:12

songyuanyao

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using static member variable of a class inside a method of this same class

Af.h

Af.cpp

1 Answers1