[Hat] hat Auxfixity.hs:92 error?

[Daniel Parry]

When attempting to use hat[0] on a reasonably simple program that
compiles fine with ghc I am faced with the following error. Could anyone
tell me what may be the cause of the error? Could there be a way in
which I could alter my program to a semantically equivalent version for
which hat would work? Or am I just using hat in the wrong way?

$ hmake -hat quineMcCluskey.lhs 
hat-trans  quineMcCluskey.lhs

Fail: AuxFixity.hs:92: Non-exhaustive patterns in case

Rather than flood inboxes I've put my program (quineMcCluskey.lhs)
online at:

http://www.srcf.ucam.org/~ddp23/quineMcCluskey.lhs

I suspect someone may recognise the bug though, even without the code?
Perhaps this problem would go away with the new version of hat?

Kind regards and thanks for any help,

Daniel

[0] Installed from: hat-2.00-1.i386.rpm

-- 
--|------| Daniel Parry (Caius) (Compsci Part II) ddp23@cam.ac.uk |-------|--
"Nobody will ever need more than 640k RAM!" [Bill Gates, 1981]
"Windows 95 needs at least 8MB RAM."        [Bill Gates, 1996]
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