Matthias Schabel wrote:
This is a somewhat tangential thought, but ... what if each release of the Boost libraries was put into its own namespace, so we have code in
namespace boost_1_38_0 { ... }
rather than in namespace boost. Then, in end user code, you just need :
using namespace boost = boost_1_38_0;
David Abrahams wrote:
It also allows multiple versions of boost to exist in the same executable without ODR violations. The ability to configure boost that way would be most welcome.
Currently I am on a library project in which I am using boost internaly, i.e. boost is not visible in the interface of my library. Since I want my users to *) use whichever version of boost library they want *) whil give them the choice to statically link my libs and *) not force myself to maintain several version of my lib due to dependencies on boost versions I pursued Matthias Schabels idea. (Altough before I had seen his post.) I have written a little perl script 'renamespace' that can be used to rename a namespace identifier for a single file or a whole project tree. The script is attached to this mail and is self-documenting. Just execute it with --help option to learn more. The script has a special short-hand mode to version an entire boost tree. In addition it modifies two boost files: version.hpp and config.hpp. The first gets an additional macro BOOST_VERSIONED_NAMESPACE and the other is modified with a namespace alias (which can be turned off by the user if needed.) The net result is that it is possible with no change to the user code to build against this versioned boost tree. One caveat: User code that needs to reopen the boost namespace has to reopen the versioned namespace of course. (This can be automated with some additional macros in the user code.) One typical case where this will be necessary is when using the serialization library. I've put the script under the boost license, so if you think it is useful I would be glad to contribute it to the tools directory. -- _________________________________________ _ _ | Roland Schwarz |_)(_ | aka. speedsnail | \__) | mailto:roland.schwarz@chello.at ________| http://www.blackspace.at