Re: [boost] Re: Boost 1.25.0 build problems?

From: Beman Dawes (bdawes_at_[hidden])
Date: 2001-10-04 14:32:11

At 03:06 PM 10/4/2001, Peter Dimov wrote:

 >From: "Beman Dawes" <bdawes_at_[hidden]>
 >> My reading of the rules is that if a standard library header requires a
 >> definition of a type (presumably because it needs a complete type), the
 >> appropriate standard library header has to be included by the
 >> implementation.  But if only a declaration is required (because the 
usage
 >> is such an incomplete type is OK), the full header doesn't have to be
 >> included.
 >
 >I think that the rules are even stricter than that. When a standard 
header
 >uses  std::string (as a complete type), for example, this most probably
 >means that std::string has been defined (although I don't think that even
 >that is guaranteed. ;-) )
 >
 >However this doesn't mean that <string> has been included, or that the
 >definitions of the templated std::string members are visible.

I'm basic my reading on the footnote for 17.4.4.1 paragraph 1, which says 
"C++ headers must include a C++ header that contains any needed definition 
(3.2)."

 >Mostly academic, of course.

Yes. For users, the rule is simple: If you use a name from the standard 
library, always include a standard library header documented as providing 
that name. Never assume some other standard library header will include it 
for you.

--Beman