Create an array that is a private static data member with a for loop

[lucian]

I want to create an array that is a private static data member with a for loop but it does not compile

in the header it is declared in the private zone: static int tableau[2]

in the cpp file i do this
int classe::tableau[2]= {for (int i=0;i<2;++i) {tableau[i]=0;};};

It does not work but if I do this int classe::tableau[2]= {0,0};
then it works. It is a simplified example but in reality I need to use a big
array this is why i need the for loop.

Thx

[xabnu]

Your syntax seems incorrect.

int classe::tableau[2] = ...

is probably trying to define a member of the class. (i've never seen a data member after the class name, and colons before, but given the way definitions of functions work it would make sense.)

So when you put {0,0}, that is legal because {0,0} represents an array. But when you put

int classe::tableau[2] = {
  for(int i = 0; i < 2; ++i){tableau[i] = 0;}
}

you would be setting the data member to be equal to an expression.

What you might do is have a function to initialize the array:

void classe::makeTableau(int * tableau, int tSize){
  for(int i = 0; i < tSize; ++i){
    tableau[i] = 0;
  }
}

[DiptenduDas]

If U want to initialize the static array to zero, then U need not to do it explicitly as "external" and "static" variables are initialized to zero iff not initialized explicitly.

[lucian]

to Diptendudas,

Acutally i don't want to have it set to zero but I am taking a simplified example to understant how to initialize a private static member array with
a for loop

[DiptenduDas]

U can do the same using a function.
Again as u have declared the variable as Private, so U can't access the same from another class.

If the variable is public one then U can access by the use of scope resolution operator (::).

Below is a small piece of code hope it may help u out.

#include<iostream>
using namespace std;

class A
{
private:
	static int statPriArray[5];
public:
	static int statPubArray[5];
	static void setArray();
	static void getArray();
};

class B
{
public:
	void getArray()
	{
		cout<<"Member of Public Static Array of A"<<endl;
		for(int i =0; i <5;i++) 
		{
			cout<<A::statPubArray[i]<<endl;
		}

		/* This will not compile as statPubArray is a member of A.
		for(int i =0; i <5;i++) 
		{
			cout<<statPubArray[i]<<endl;
		}
		*/

		/* This will not compile as statPriArray is a static member of A but private one.
		for(int i =0; i <5;i++) 
		{
			cout<<A::statPriArray[i]<<endl;
		}
		*/
	}
};

int A::statPriArray[] = {0};
int A::statPubArray[] = {0};

void A::setArray()
{
	cout<<"Setting both Private as well as Public Static Array"<<endl;
	for(int i =0; i <5;i++)
	{
		A::statPriArray[i] = i+1;
		A::statPubArray[i] = i+5;
		/*
		///Also can be use as below as both member of A
		statPriArray[i] = i+1;
		statPubArray[i] = i+1;
		*/
	}
}

void A::getArray()
{
	cout<<"Member of Public Static Array"<<endl;
	for(int i =0; i <5;i++) 
	{
		cout<<statPubArray[i]<<endl;
	}

	cout<<"Member of Private Static Array"<<endl;
	for( i =0; i <5;i++) 
	{
		cout<<statPriArray[i]<<endl;
	}
}

int main()
{
	A::getArray();
	A::setArray();
	A::getArray();

	B* b = new B();
	b->getArray();
	return 0;
}