Passing array to stringstream - stringstream

Question

This is something I had never noticed but for some reason you can't do something like
sstr << myarray;
If you do that "sstr" would contain the address of "myarray",You would have to do
for(int i;i < sizeof(myarray);i++)
{
sstr << myarray[i];
}
I would like to know why does this happens, I don't remember ever having to do that, but personally I think sometimes reality itself changes just to annoy me.

Answer 1

You need to define your own stream operation for an array to be able to display it.
#include <iostream>
#include <vector>
using namespace std;
template <typename T>
class mydata
{
public:
mydata(int size = 0) { for (int i = 0; i < size; i++) add(0); }
~mydata() { }
void add(T x) { data.push_back(x); }
void remove(int pos) { data.erase(data.begin() - pos); }
T& operator[](int pos) { return data[pos]; }
friend ostream& operator<<(ostream& os, const mydata<T>& name) {
for (int i = 0; i < x.data.size(); i++) os << x.data[i] << " "; return os; }
private:
vector<T> data;
};
That would be a standard class for encapsulating your data. If you wanted to do an operation like mydata<int> b(8); b[7] = 8; you can. The reason the code for the << operator is inside the class is because templates requires typename specific code to be inside the template itself.
Finally, this is how this code can be implemented.
int main()
{
mydata<char> charData;
mydata<int> intData;
for (int i = 0; i < 20; i++) {
charData.add(65+i);
intData.add(i);
}
cout << charData << endl;
cout << intData;
cin.get();
return 0;
}
The output looks like this:
A B C D E F G H I J K L M N O P Q R S T
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19