🚀 go-pugleaf

harald@bion.kth.se (Harald Winroth) writes:

>There is a common pattern in which a base class implements an algorithm but
>leaves some of the steps unspecified (in C++ typically as pure virtual
>functions). These steps are later defined in subclasses. The current 
>standard draft prevents this pattern to be used in constructors, which I
>think is unfortunate.

I agree that the current rules for deploying virtual functions in
constructors and destructors can be inconvenient at times.  But they
have a distinct advantage.  The rules, written as they are, guarantee
that no member function of a class (other than one of its
constructors) will be called until all the members and bases of that
class have been initialized.

If the rules allowed virtual deployment in constructors or
destructors, then functions could be called in classes where the
members and/or bases had not been initialized, or had been destructed.
And this, IMHO, would be untennable.
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