[Hat] hat Auxfixity.hs:92 error?

[Malcolm Wallace]

Daniel Parry <ddp23@cam.ac.uk> writes:

> When attempting to use hat[0] on a reasonably simple program that
> compiles fine with ghc I am faced with the following error.
> 
> $ hmake -hat quineMcCluskey.lhs 
> hat-trans  quineMcCluskey.lhs
> 
> Fail: AuxFixity.hs:92: Non-exhaustive patterns in case

This is a bug in hat-trans, which appears to be (sort of) fixed in
the current CVS version.  The next release of Hat is due in a couple
of weeks, but if you can't wait, and would prefer not to use CVS,
there is a workaround: in your program, replace uses of the constant
-1 with (negate 1), excepting patterns of course.

Regards,
    Malcolm