Re: Boost 1.25.0 build problems?

From: williamkempf_at_[hidden]
Date: 2001-10-08 09:27:01

--- In boost_at_y..., Howard Hinnant <hinnant_at_t...> wrote:
> On Saturday, October 6, 2001, at 08:17  AM, Kevlin Henney wrote:
> 
> >> Maybe you ought to write up a defect report.  It will be easier 
for 
> >> the LWG
> >> to understand the issue if you boil it down to a very simple 
piece of 
> >> code
> >> that you want to know is or isn't conforming.
> >>
> >> Let's see.  Something like this:
> >>
> >>   #include <stdexcept>
> >>
> >>   class lock_error : public std::runtime_error
> >>   {
> >>   public:
> >>       lock_error() : std::runtime_error("thread lock error") { }
> >>   };
> >>
> >>   Is this conforming code?  Note the lack of #include <string>,
> >>   that std::runtime_error() takes a const string& argument, and
> >>   there is no constructor taking a const char*.
> >>
> >> Post it on comp.std.c++ with a subject that begins "Defect 
Report:"
> >
> > I believe that this issue (between <stdexcept> and <string>) is a 
known
> > problem, although I don't know if it's yet a DR. It has at least 
been
> > mentioned in passing by myself, Howard Hinnant and a couple of 
others at
> > one or other of the ISO meetings in the last year (and the cyclic
> > dependency problem was also the basis for a general solution I 
wrote up
> > in http://www.cuj.com/experts/1911/henney.htm).
> 
> Martin Sebor has repeatedly tried to get a dr issue going in this 
> general area (not specifically with <string> and <stdexcept>) and 
> failed.  This issue came up in the hs_conformance reflector prior 
to the 
> CUJ Vendor Review article.  In that case it did deal specifically 
with 
> <string> and <stdexcept>.
> 
> I believe the standard should say more about this issue, but I to 
not 
> have the standard-eze in hand.  Several people have proposed rules, 
and 
> I believe that at least an informal consensus may be forming.  My 
> personal opinion, which has been influenced by similar words 
already 
> spoken by noted experts, is that the standard should say something 
like:
> 
> > If you explicitly use a standard defined name, then you must 
explicitly 
> > include the associated header.  Otherwise you do not have to 
include 
> > the header, even if you are implicitly referring to said object.
> 
> Of course the above "rule" would have to be encoded in standard-eze 
so 
> that only high priests are capable of interpreting its true 
meaning. ;-)
> 
> Under this rule, Beman's example would be conforming because it 
only 
> implicitly refers to std::string, not explicitly.  Thus #include 
> <string> is not necessary.  If the example were changed to:
> 
>         lock_error() : std::runtime_error(std::string("thread lock 
> error")) { }
> 
> then #include <string> becomes necessary.
> 
> Just my .02.

I'm glad others feel the same as I.  Do I need to try and propose yet 
another defect on this subject or is there any progress occuring 
within the comittee on at least discussing this issue?

Bill Kempf