Adding Instance of Sub-Class to map array

Question

In C++, I have the following map array:

map<string, Module> modules;

And the following code to define the Module class:

class Module {
    public:
        const char** run();
};

And the following subclass that implements all required methods from it's parent:

class Wsiv : public Module {

And the following code block after the vector:

#ifndef NWSIV
    modules["wsiv"] = new Wsiv; // Add the WSIV module if it's not disabled at compile time.
#endif

But when I compile this all (I know everything is being included) it gives me this error:

../src/main.cpp:38:25: error: expected type-specifier before 'Wsiv'
   modules["wsiv"] = new Wsiv; // Add the WSIV module if it's not disabled at compile time
.
                         ^
../src/main.cpp:38:25: error: expected ';' before 'Wsiv'

Because Wsiv extends Module, I should be able to initialize an instance of Wsiv and assign it as a value in an array of Module classes. I should be able to cast one type to the other. How can I fix this?

The code makes no sense. `new WSIV` produces a `WSIV *`, not a `Module`. — Kerrek SB, Sep 30 '14 at 22:02
but `WSIV` extends `Module`. How do I turn a `WSIV *` into a `Module`? — Ethan McTague, Sep 30 '14 at 22:06
@KerrekSB: the first point i noted that the code makes no sense was use of `const char*` as key. — Cheers and hth. - Alf, Sep 30 '14 at 22:06
@user3053430: a pointer to X isn't an X. howver, start by replacing `const char*` with `std::string`. also don't use uppercase class names. note if you just dereference then you'll both get slicing and a memory leak. — Cheers and hth. - Alf, Sep 30 '14 at 22:07
Will some part of using allcaps class names cause an error in my program? — Ethan McTague, Sep 30 '14 at 22:10
@user3053430: in addition to all advice already given, it's a good idea to *stop presuming*. — Cheers and hth. - Alf, Sep 30 '14 at 22:11
I don't quite understand what you mean. My apologies, but I am quite inexperienced with C++ and am used to java, in which my code would work just fine (with syntax adjustments). — Ethan McTague, Sep 30 '14 at 22:12
It looks like you didn't `#include` the file that contains the `Wsiv` definition, or you aren't being consistent in the capitalization when you spell it. — Mark Ransom, Sep 30 '14 at 22:20

Adding Instance of Sub-Class to map array

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