Re: avoid inheritance from std::map
AnonMail2005@gmail.com wrote:
On Dec 15, 10:03 am, "Hicham Mouline" <hic...@mouline.org> wrote:
we have bits of code where we inherit from std::map.
Why again shouldn't one inherit from STL containers in the C++ runtimes?
The proposal is to write a
template <typename Key, typename Value>
class MapDecorator {
//replicate map's interface here and simply forward all calls to m_
private:
std::map<Key,Value> m_;}
and then inherit from MapDecorator <....>
I agree one shouldn't inherit from std::map, though I don't remember why,
However the above seems to me redundant?
regards,
Ths simplest answer is that std::map does not have a virtual
destructor. So if you are using pointers to the base class and you
delete them, the derived class detructor will not be properly called.
That's the reason I'm hearing quite often. But which of those classes do you
actually use polymorphically? I never allocated an std::map dynamically. Why
would I? And why would I want to have a pointer to std::map pointing to an
object of a class derived from it? Since I don't see any reason for doing
that, I also don't see any reason to not derive from standard containers.
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