[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!


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