[boost] Re: question on static data members of class templates

From: Anthony Williams (anthwil_at_[hidden])
Date: 2002-09-17 10:26:08

 Markus Schöpflin writes:
 > Jaap Suter wrote:
 > > 
 > > I think http://www.boost.org/more/int_const_guidelines.htm will help you
 > > out...
 > > 
 > 
 > Either I'm too blind to see it or it is not there.
 > 
 > But reading the bible (read: the c++ standard), section 5.19 tells
 > me that is should look in 9.4.2 (static data members). And sentence
 > 4 of 9.4.2 tells me that "The member shall [still] be defined in
 > namespace scope if it is used in the program ..."
 > 
 > 14.5.1.3 (Static data members of class templates) says that
 > "A definition for a static data member may be provided in a
 > namespace scope enclosing the definition of the static member's
 > class template."
 > 
 > So this looks like the code I posted should be legal?

Yes this is legal. The restriction that "there shall be exactly one definition
of a static data member that is used in a program; no diagnostic required",
does not apply to static data members of templates, so long as the duplicate
definitions are in every sense identical (see 3.2p5).

Anthony