While investigating test failures with Boost.Foreach, I found this in Boost.Range's documentation for extending the Range library: http://boost.org/libs/range/doc/boost_range.html#minimal_interface This seems to suggest that the only way to extend Boost.Range is for user-defined types to implement a std-container-like interface, with nested iterator and const_iterator types, and begin() and end() member functions. Is this really the intention? I seem to recall some discussion about a more accomodating extensibility mechanism that makes allowances for non-std-container-like user-defined range types. In fact, Boost.Foreach assumes such an interface, with disastrous results. What became of Boost.Range's extensibility mechanism? Is it documented anywhere, and I'm just not seeing it? -- Eric Niebler Boost Consulting www.boost-consulting.com