[Haskell-cafe] Existential type within a record ... bad?
Scott West
swest3 at cogeco.ca
Tue Jul 27 14:52:35 EDT 2004
Hello all,
Just got an interesting error, which I can't really understand (but that DOES happen a lot...). Trying to work with existention types, record types, and wrapping the whole thing up in a nice IORef for my uses:
data ETable = forall a. EditableTable a => ETable a
data GuiRecord = GuiRecord
{gtable :: ETable,
moz :: MozEmbed,
pos :: Position,
ent :: Entry}
type GuiState = IORef (GuiRecord)
Generates the following error:
Couldn't match `* -> Type bx' against `*'
In the type synonym declaration for `GuiState'
Anyone have any ideas?? Thanks in advance!
Regards,
Scott
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