With an eye to verifying the existence of library using templates which would not benefit from explicit type constraints I went through some of the documentation of AFIO. I posted a log of my notes as I went through it here: http://rrsd.com/blincubator.com/open-content/#comment-26 Of necessity, it sort of rambles around before it gets to the main point. That's because I had to start at the beginning in order to have enough context to understand it. Short version a) I don't think this library demonstrates that type constraints wouldn't help. In fact I think the opposite. b) This further reinforces my view that DOxygen is not a great system for writing C++ documentation. c) AFIO is much more complicated than I think it has to be - but I can't prove this because its so hard to understand anything about it. Robert Ramey -- View this message in context: http://boost.2283326.n4.nabble.com/Concepts-Definition-Was-GSoC-Boost-Hana-F... Sent from the Boost - Dev mailing list archive at Nabble.com.