Chameleon is a Haskell-style language which provides a flexible overloading mechanism based on Constraint Handling Rules (CHRs). The latest version comes with a type debugger. Our approach handles Hindley/Milner types with Haskell style overloading (including advanced features such as functional dependencies etc.) For more details check out http://www.comp.nus.edu.sg/~sulzmann/chr/publications.html for papers describing Chameleon, http://www.comp.nus.edu.sg/~sulzmann/chameleon/ for the latest release including a number of examples. Cheers, Martin