Why does my .push_back() give me an error? (C++)

Question

I initialized a vector of pointers called "antiviral_data", and am able to use antiviral_data.push_back without problems. But when I try to do the same thing with "viral_data" I get an error, because the compiler thinks I am redeclaring "viral_data":

vector<virus*> viral_data;
vector<virus*>::iterator vI;
viral_data.push_back(new X1(9, 9, 'X')); //I get the error on this line
vector<antivirus*> antiviral_data;
vector<antivirus*>::iterator aI;

(FYI: antiviral_data is in another function, this is a header file)

EDIT: X1 is a class derived from virus.

Answer 1

Well, I figured out the answer to my question about thirty seconds after I posted it, apparantly you can't use any function outside of main() or another function, so you have to put .push_back() in a different function.

Answer 2

If the compiler tells you it thinks you're redeclaring a name, maybe you should wonder why it thinks so.

Probably, it's because you did redeclare the name.

Since you have the code in a header file, chances are you include that file twice. Line numbers in error messages are not always so very accurate...

If that would be the case, you can get help from so called "include guards": prepend the header file with something like

#ifndef HEADER_INCLUDED
#define HEADER_INCLUDED 
...
... your actual header
#endif

(or on VC, you can use

#pragma once

)