Re: Policy-based class design or inheritance?
Vincent wrote:
On 30 Set, 20:59, "Martin T." <0xCDCDC...@gmx.at> wrote:
Vincent wrote:
Hi all,
suppose we can choose between two approaches:
1) First approach (policy-based class design)
template <typename OutputPolicy>
class A {
...
public:
void print() {
OutputPolicy::print("...");
}
};
(...)
2) Second approach (classic inheritance)
class A {
...
public:
virtual void print() = 0;
}
(...)
(...)
Personally, I would never use #1 if there are no strong reasons why #2
is clearly worse, because at my current environment it would just
confuse people.
In my opinion solution #2 is not so bad, but #1 is better. Why?
Because it is clear, elegant and not error prone (no need to think of
virtual tables, pure virtual functions, polymorphism, and so on).
What do you think?
I think that if you want a compile-time selection of the output policy
and do not need to use class A polymorphically, then #1 is better. With
the exception that it's worse if you work with people that take a fright
when they see templates. If such people will have to work with the code,
then #2 may be better from a practical point of view.
br,
Martin
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