returning a vector

[kes103]

I'm trying to figure out how I can return a vector from a method
so that I can print the results in main().
Example:

class test{
    public:
    vector <string> A(vector <string> a, vector <string> b){
            vector <string> retval;
             retval.push_back("test");
             return (retval);
    }
};
//
int main(void){
     test p;
     p.A;
     cout<<A[0];
}

When I do this I get a compiler error until I copy

vector <string> retval;

into the main function. However, this reinitializes the retval vector. How, can I code this so that I don't have to reinitialize the vector in main?
Thanks in advance.

[rmullen3]

Um, you're not passing anything to the method A()...

[nextus]

and also when you do call functions even thought it takes no arguments always end in parethesis

like

a.blah();

[kes103]

OK, sorry. that code should have been----

class test{
    public:
    vector <string> A(vector <string> a, vector <string> b){
            vector <string> retval;
             retval.push_back("test");
             return (retval);
    }
};
//
int main(void){
     test p;
     p.A(a,b);
     cout<<retval[0];
}

[orbitz]

Umm...where are a and b being declared? and retval for that matter.

[kes103]

ok, again, of course a, b have to be declared in main() as well, and I suppose retval does too, like so:

class test{
    public:
    vector <string> A(vector <string> a, vector <string> b){
            vector <string> retval;
             retval.push_back("test");
             return (retval);
    }
};
//
int main(void){
     vector <string> a;
     vector <string> b;
     vector <string> retval;
     test p;
     p.A(a,b);
     cout<<retval[0];
}

but the point is, when I redeclare retval in main, it is reintialized
and the return value(s) are lost. How do I avoid this?

[PJYelton]

Retval goes out of scope when the function terminates. If you want to access it the way you are trying to access it, you need to make it a member of the test class, not declare it within the function. OR if you don't want it a member and only want it to return a vector, then you need to declare a vector in main and have the function return a value to it like so:

vector<string> retVal;
retVal=p.A(a,b);
cout<<myVec[0];

[orbitz]

Like PJYelton said, you need to assign a value to retval. It is just like any other function with a return value.