Docs

library/Hasql.hs

@@ -37,15 +37,21 @@ import qualified Hasql.IO as IO
 data Connection =
   Connection !LibPQ.Connection !Bool !PreparedStatementRegistry.PreparedStatementRegistry
 
+-- |
+-- An error of the result-decoder.
 data ResultsError =
   -- |
   -- An error on the client-side,
   -- with a message generated by the \"libpq\" library.
   -- Usually indicates problems with connection.
   ClientError !(Maybe ByteString) |
+  -- |
+  -- Decoder error details.
   ResultError !ResultError
   deriving (Show, Eq)
 
+-- |
+-- Decoder error details.
 data ResultError =
   -- | 
   -- An error reported by the DB. Code, message, details, hint.
@@ -77,14 +83,23 @@ data ResultError =
   UnexpectedAmountOfRows !Int
   deriving (Show, Eq)
 
+-- |
+-- An error during the decoding of a specific row.
 data RowError =
+  -- |
+  -- Appears on the attempt to parse more columns than there are in the result.
   EndOfInput |
+  -- |
+  -- Appears on the attempt to parse a @NULL@ as some value.
   UnexpectedNull |
+  -- |
+  -- Appears when a wrong value parser is used.
+  -- Comes with the error details.
   ValueError !Text
   deriving (Show, Eq)
 
 -- |
--- A connection acquistion error.
+-- Possible details of the connection acquistion error.
 type ConnectionError =
   Maybe ByteString