10 May
2006
10 May
'06
9:13 a.m.
On 10.05 13:27, Otakar Smrz wrote:
data ... = ... | forall b . FMap (b -> a) (Mapper s b)
... where FMap qf qc = stripFMap f q
the GHC compiler as well as GHCi (6.4.2 and earlier) issue an error
My brain just exploded. I can't handle pattern bindings for existentially-quantified constructors.
You can rewrite the code in a way that GHC accepts it. Just avoid pattern binding your variables. I had the same problem in HAppS code and needed to lift some code to the top level to solve it. - Einar Karttunen