Re: Are throwing default constructors bad style, and if so, why?

From:
Andrei Alexandrescu <SeeWebsiteForEmail@erdani.org>
Newsgroups:
comp.lang.c++.moderated
Date:
Sun, 28 Sep 2008 15:41:13 CST
Message-ID:
<48DF95D7.3010303@erdani.org>
rani_sharoni@hotmail.com wrote:

On Sep 22, 5:27 pm, David Abrahams <d...@boostpro.com> wrote:

That's just move semantics AFAICT, which should be nonthrowing. If you
mean something else, please explain.


While ago I sent you "improving STL exception specifications" draft
(no offenses for lack of interest) with the following "observation":
Non throwing move constructor implies non throwing default constructor
given non throwing clear operation.

For example consider the following:
string str1("abc");
string str2 = std::move(str1); // no throw in current C++0x
str1.clear(); // str1 is now like default constructed string

Therefore non throwing default constructors seem quite important for
useful move semantics (e.g. standard containers).

Rani

BTW - I'm willing to share the paper if someone is interested.


Thanks! If you could share a link to it here, we could all benefit from it.

Andrei

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