Thomas Davie
Note in the case statement that the variable fv59v12v59v12n is bound in the second case, but used in the first... As is the variable ftyp.
Well, strictly speaking, those variables are used in the case discriminant, rather than the first case alternative, but your point stands. The variables are not bound until the pattern-match that follows evaluation of the discriminant. i.e. case foo bar of (R (foo,bar) baz -> ... As far as I can see, the fault in hat-trans is due to the combination of a local pattern deconstruction (the pair), with a numeric pattern (0).
where (0, typ) = Map.findWithDefault (0, TLit x) x table
The numeric pattern is translated to a cguard, but the tuple pattern is translated to a case. So the numeric pattern cguard tries to use the value from the tuple case pattern match, whilst itself being the discriminant of the case. Olaf's department. :-) Regards, Malcolm