STL + Polymorphism?

std::vector<MemoryObject*> list;

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Original post by joanusdmentia Nope, std::vector isn't a linked list, it's a dynamic array. Also, it doesn't store a pointer to the type you specify, it stores instances of the complete type. So if you specifying MemoryObject it will store complete MemoryObjects, not pointers to them.

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Original post by Endar Quote: Original post by joanusdmentia Nope, std::vector isn't a linked list, it's a dynamic array. Also, it doesn't store a pointer to the type you specify, it stores instances of the complete type. So if you specifying MemoryObject it will store complete MemoryObjects, not pointers to them. That's why if you want to store both DMemoryObject and SMemoryObject types in the same vector, you need to store MemoryObject* and create each DMemoryObject and SMemoryObject on the heap using 'new'. Else, you could write a container that will keep several different types of different sizes, but then you'd end up with a lot of wasted space. But with the pointer being used, if later on you decide to create another type of memory object, you can just start storing it right away, because it too will be derived from MemoryObject, so you'll be able to access it with a MemoryObject*. You can't use references because vector uses pointers and you can't legally have pointers to references or arrays of references (so VC++ 6 says).

template <class T>class array{private:	T* array;	unsigned int size;public:	array(unsigned int s)	{		array = new T[s];		size = s;	}};

MemoryObject* mem_array[50];	// instances of MemoryObject*int int_array[50];		// instances of int

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Original post by dbzprogrammer Doesn't vector contain a linked list

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with a pointer

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Would that do the trick or what?

void old_function_expecting_a_c_array( char * data , size_t n ) {    //use array[0..n-1]}int main () {    std::vector< int > some_data( ... );    //fill some_data or specify starting data in some_data's ctor    //since the C++ standard makes certain guarantees (such as that std::vector    //will allocate all it's items directly next to each other) - this will work    old_function_expecting_a_c_array( & some_data[0] , some_data.size() );}

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If not, then I would know what to do. Could I perhaps have a vector of references?

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Original post by Promit Suit yourself. But it's time wasted on unimportant things.

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Original post by Kuladus Quote: Original post by Promit Suit yourself. But it's time wasted on unimportant things. It's a learning exercise. Not a waste of time.

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Original post by Promit Quote: Original post by Kuladus Quote: Original post by Promit Suit yourself. But it's time wasted on unimportant things. It's a learning exercise. Not a waste of time. There are more important/useful things to learn than this low level hackery. Just...so many more compelling things to play with.