[database-devel] Postgresql enum type conversions

[Luke Hoersten]

I'm trying to use postgresql enum types to represent Haskell types
like in the code snippet below but an receiving the following error:


"Incompatible {errSQLType = "x", errHaskellType = "Text", errMessage =
"types incompatible"}"

In other areas of my code (not shown) I'm successfully using Text to
convert to and from Postgersql enum types but it doesn't seem to work
in the case below. Any ideas what I'm doing wrong?

Thanks, Luke




import           Database.PostgreSQL.Simple.FromField
(FromField, fromField)import
Database.PostgreSQL.Simple.FromRow          (FromRow, field,
fromRow)import           Database.PostgreSQL.Simple.SqlQQ
(sql)

data X = X Float
       | Y Float

buildX :: Text -> Float -> XbuildX "x"      = XbuildX "y"      = Y

instance FromField (Float -> X) where
    fromField f v = buildX <$> fromField f v

instance FromRow X where
    fromRow = field <*> (field :: RowParser Float)
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