Re: Deriving from concrete types
Holger Sebert wrote:
I know that is in general a bad idea to derive from concrete types.
....because when you delete them via a pointer to the baseclass, the
destructor is not invoked polymorphically, leading to undefined behaviour.
However, I wonder if it is o.k. if the derived class does not add any data
members but only extends the interface.
Still undefined behaviour.
SpecialIntVector v;
v.resize( 1000 );
v.doSomethingSpecial();
Where are the problems with this approach?
As said above. If that doesn't apply, there is still another question left:
why? std::vector has no virtual functions you could overwrite and no
protected members you would get access to, so what's the gain?
I'd rather do this:
vector<float> v(1000);
DoSomethingSpecial(v);
...or even this:
vector<float> v(1000);
DoSomethingSpecial(v.begin(), v.end());
...or perhaps the equivalent using ranges.
Uli
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