Dear all, Since its inception my dimensional library has been built around a unary type-level representation of integers (NumTypes) defined in the Numeric.NumType module. This module has proven itself useful outside the context of dimensional and after dragging my feet for a long time I've finally gotten around packaging it up in its own library: numtype[1]. The Numeric.NumType module is completely self-contained (only imports Prelude) and is heavily commented in a narrative manner inspired by Oleg Kiselyov's expositions. I believe it provides a good case study for type-level programming with multi-parameter type classes and functional dependencies. Addition, subtraction, division, and multiplication of NumTypes is supported. NumTypes have no value-level representation but can be converted to any Num instance with the 'toNum' function. The numtype library has two significant short-comings: * Minimal haddocks -- as with my dimensional library the literate Haskell source code is the documentation. The flip-side is that the code is very well-commented. * Due to the unary implementation the practical size of the NumTypes is severely limited, making them unsuitable for large-cardinality applications. If you will be working with integers beyond (-20, 20) this package probably isn't for you. (If the second bullet is a show-stopper Edward Kmett's type-int[2] library may be a better choice. Peter Gavin's tfp[3] library also provides type-level integers but uses type families instead of MPTCs and fundeps. I cannot vouch for either of these libraries as I haven't used them.) Numtype version 1.0 can be downloaded from Hackage or the dimensional project page[4]. I've also updated dimensional to version 0.8 with the Numeric.NumType module removed and Julian 'year' and 'century' units added. Enjoy! Thanks, Bjorn Buckwalter [1]: http://code.google.com/p/dimensional/wiki/numtype [2]: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/type-int [3]: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/tfp [4]: http://dimensional.googlecode.com