[Haskell-cafe] Re: help with happy/alex

Simon Marlow simonmarhaskell at gmail.com
Thu Nov 23 04:30:17 EST 2006

robert bauer wrote:
> Hi,
> I have a .y and .x file.  The alex -g _.x gives me a .hs file and happy -g -a -c _.y gives me a .hs file.
> I then use ghc -c alex.hs to get a a .o and a .hi file.  This works great.
> Unfortunately
> ghc -c happy.y doesn't work -- it says that it the module name for the lexer doesn't match.  I've attached the
> .y and .x files.
> Also,  I cannot figure out what I need to do in the parser to call the lexer and I don't know how to kick start the
> parser -- I have no clue what to put in third, main.hs, module.
> Any help would be appreciated.

You have a typo in the module name in TVScriptLexer.x.  As for tying it 
together, I suggest taking a look at some of the examples, eg. 
http://darcs.haskell.org/alex/examples/tiny.y from the Alex distribution.


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