Eric Niebler wrote:
I have heard unconfirmed rumors that someone has a script that takes Boost code and moves it into a different top-level namespace. Does such a script really exist?
The goal is to be able to automatically munge Boost code so that several versions can be used in parallel without conflicts. If anybody is currently doing this, I'd love to hear from them. To use multiple versions in parallel wouldn't you also need to mangle the include guard symbol names to allow each version to independently remember which headers have been processed?
Yes, and all macro names would need to change, too.
Not only this. Consider that some Boost file contains this: #include "boost/config.hpp" #include "boost/detail/workaround.hpp" // ... The physical meaning of "boost/..." is resolved thanks to the appropriate -I compiler option. If you want to have several versions in parallel, then I presume that you want to #include them together from your project - in which case the meaning (resolution) of "boost/..." would need to be different in each version, so that there are physically multiple header trees. This cannot be done with multiple -I options. This means that not only namespace names and macros, but also #include paths in Boost files should change to use separate path prefixes, like: #include "boost_X/config.hpp" #include "boost_X/detail/workaround.hpp" // ... Hint: Vera++ can do this. I already have transformation scripts that do all three tricks. They will be released together with one important bugfix. -- Maciej Sobczak * www.msobczak.com * www.inspirel.com