Define and initialize stl constant in one line

Question

I have a class:

Temp.h:
[...]
class Temp{
public:
    Temp(vector<vector<double> > vect);
    const static Temp VAR1;
    const static Temp VAR2;
    ...

};

I want to initialize VAR1 and VAR2 using array of doubles: {{0,1,0,1},{1,0,1,0}}. But I cannot do this like this:

const Temp::VAR1(...);

, because there is no 'one-line' operator to construct vector of vectors from an array of arrays. I thought about building structure, like:

B{
    vector<vector<double> > vect;

    B& add (double[] a, int number) {... 
    push elements from array to vector and add this vector to vect ...
    return *this;
    }

    Temp build() {return Temp(vect);}
}

But when I call:

 B().add({0,1,0,1},4).add({1,0,1,0},4).build();

Compiler doesn't recognize {0,1,0,1} as an array, but as a double* and I cannot change it.

Is there any option to create some method or something similar to initialize const static member in more lines than one?

I hope I wrote simple enough, if not, I'll edit it later.

Answer 1

In C++11, use the uniform initialisation syntax:

const Temp::VAR1{{0,1,0,1},{1,0,1,0}};

If you have to remain compatible with C++03, I'd recommend using boost::assign:

const Temp::VAR1 = list_of(list_of(0)(1)(0)(1))(list_of(1)(0)(1)(0));

Answer 2

Write a static function that initializes it:

Temp InitTempVar1()
{
    vector<vector<double> > init;
    // initialize init...
    return Temp(init);
}

Temp InitTempVar2()
{
    vector<vector<double> > init;
    // initialize init...
    return Temp(init);
}

const Temp Temp::VAR1 = InitTempVar1();
const Temp Temp::VAR2 = InitTempVar2();