As a side note I would really like to see libraries, which are tailored for Boost, use the Boost Config C++ feature testing macros to put out preprocessor #error messages when a feature that it needs is not supported during compilation, rather than letting the compiler simply fail because the construct in code cannot be parsed at the C++ conformance level the code expects.
This should happen during configure step, so that the user gets an error before even building the library.
A library's headers may have much lower demands on the C++ version than the source code. So your headers should still do feature checking and #error out. Niall -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/