on Fri Dec 19 2008, "Vladimir Batov" <batov-AT-people.net.au> wrote:
It seems I did it again. :--( Just noticed that I misread the following excerpt of Scott's email. Apologies and corrections further below.
Take, for example, a map<string, uuid>. No default constructor means that you can't use operator[],
First, my preference is to *have* the default constructor -- we disagree on its behavior as I'd like the default constructor to *be part* of the constructors family (constructing a valid object) and you insist on the default constructor being an exception.
I think the terminology "valid object" is misleading here. A NULL pointer is valid. An uninitialized pointer is... marginally valid. I don't think anyone is suggesting that uuid() should produce an object that can only be assigned to or destroyed.
The latter is not how the language interprets the default constructor.
I can't imagine what you mean by that.
Therefore, me not happy. IMHO that deviation of the meaning from the letter of the language is unacceptible.
Second, even if I cannot use operator[], so what? std::fstream has no default constructor. std::list has no operator[], std::vector has no push_front(). That did not stop anyone from using those classes. What the lack of those "features"
Do you really mean to imply that push_front, operator[], et. al. are not legitimate features? -- Dave Abrahams BoostPro Computing http://www.boostpro.com