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

Erik de Castro Lopo mle+hs at mega-nerd.com
Sun Mar 9 08:47:07 UTC 2014

Ömer Sinan Ağacan wrote:

> 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.

Also look at the DDC codebase:


Erik de Castro Lopo

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