[Haskell-cafe] looking for alex+happy examples that uses location annotated tokens and location information in err msgs

Does anyone have any example alex+happy programs that uses location location annotated tokens and location information of token while reporting parse errors? I already wrote lexer and my function type is something like:

runLexer :: String -> [(Token, AlexPosn)]

where AlexPosn type contains location information. But I have no idea how can I use that in happy to parse and use location information in parse error messages. There are lots of examples in interwebs but as far as I can see none of them works on location-annotated tokens. Thanks.. --- Ömer Sinan Ağacan http://osa1.net