C string in classes

Question

I realise this is a silly question, but it's perplexing and annoying since something that should function isn't. 

I'm using the GCC compiler with Code Blocks, and I'm trying to construct a string variable in my class.

#ifndef ALIEN_LANGUAGE
#define ALIEN_LANGUAGE

#include <string>

class Language
{
    public:

    private:
        string str;
};

#endif

Strange enough, my compiler halts me with an error saying this:

C:\Documents and Settings\...|11|error: `string' does not name a type|
||=== Build finished: 1 errors, 0 warnings ===|

For some reason, it is unable to locate the class "string," despite the fact that my main.cpp is able to identify "#include," but my language class is not.

This is the essential point. 

I wrote it hastily to check if the main programme could see the string file:

//main.cpp

#include <iostream>
#include <string>
#include "alien_language.h"

using namespace std;

int main()
{
    string str;

    return 0;
}

Does anyone know what's going on?

Answer 1

The std namespace contains the string class. You need change the class to something like this:

class Language
{
    public:

    private:
        std::string str;
};

This can also be included at the top of the header file, although it is not recommended:

using namespace std;