Re: static map problem

From:
"VSR" <vraghuvamshi@gmail.com>
Newsgroups:
comp.lang.c++.moderated
Date:
28 Apr 2006 09:13:43 -0400
Message-ID:
<1146143224.377693.185040@j33g2000cwa.googlegroups.com>
Belinda,

You should not be facing any runtime issues. You should at most be
facing Linker errors at compile time.

To be able to resolve your statically defined object they way you are
doing, I would recommend building your library as a static library
instead of dynamic.

But from a design standpoint, a cleaner approach would be to implement
your ClassA, b and c as singleton objects. Refer to Design patterns by
Eric,Gamma etal.

Other than that, your stuff should work. Here is how your code should
look:

in library header:
=============
class ClassA {
public:
        ClassA(){};
        ~ClassA(){};
        void foo(){std::cout << "ClassA::Foo" << std::endl;}
protected:
        static std::map<std::string,std::string> myMap;
};

in library cpp:
==========
std::map<std::string,std::string> ClassA::myMap;

In Client cpp:
=========
class ClassB: public ClassA
{
public:
        int whatever;
        void foo()
        {
                ClassA::foo();
                std::cout << "ClassB::Foo" << std::endl;
                myMap.insert(std::make_pair("TestKey","TestVal"));
                std::map<std::string,std::string>::iterator pos = myMap.begin();
                while(pos != myMap.end())
                {
                        std::cout << "myMap key: " << pos->first.c_str()
                                << ", myMap val: " << pos->second.c_str() << std::endl;
                        ++pos;
                }
        }
};

static ClassB cb;

int _tmain(int argc, _TCHAR* argv[])
{
        cb.foo();
        return 0;
}

Hth.
-Vinayak Raghuvamshi

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