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1. mpsAvoidHsKeyword :: MkPersistSettings -> Text -> Text

   persistent	Database.Persist.TH

   Customise function for field accessors applied only when the field name matches any of Haskell keywords. Default: suffix "_".

2. setImplicitIdDef :: ImplicitIdDef -> MkPersistSettings -> MkPersistSettings

   persistent	Database.Persist.TH

   Set the ImplicitIdDef in the given MkPersistSettings. The default value is autoIncrementingInteger.

3. data ImplicitIdDef

   persistent	Database.Persist.TH.Internal

   A specification for how the implied ID columns are created. By default, persistent will give each table a default column named id (customizable by PersistSettings), and the column type will be whatever you'd expect from BackendKey yourBackendType. For The SqlBackend type, this is an auto incrementing integer primary key. You might want to give a different example. A common use case in postgresql is to use the UUID type, and automatically generate them using a SQL function. Previously, you'd need to add a custom Id annotation for each model.

   User
   Id   UUID default="uuid_generate_v1mc()"
   name Text
   
   Dog
   Id   UUID default="uuid_generate_v1mc()"
   name Text
   user UserId
   

   Now, you can simply create an ImplicitIdDef that corresponds to this declaration.

   newtype UUID = UUID ByteString
   
   instance PersistField UUID where
   toPersistValue (UUID bs) =
   PersistLiteral_ Escaped bs
   fromPersistValue pv =
   case pv of
   PersistLiteral_ Escaped bs ->
   Right (UUID bs)
   _ ->
   Left "nope"
   
   instance PersistFieldSql UUID where
   sqlType _ = SqlOther UUID
   

   With this instance at the ready, we can now create our implicit definition:

   uuidDef :: ImplicitIdDef
   uuidDef = mkImplicitIdDef @UUID "uuid_generate_v1mc()"
   

   And we can use setImplicitIdDef to use this with the MkPersistSettings for our block.

   mkPersist (setImplicitIdDef uuidDef sqlSettings) [persistLowerCase| ... |]
   

   TODO: either explain interaction with mkMigrate or fix it. see issue #1249 for more details.

4. mpsAvoidHsKeyword :: MkPersistSettings -> Text -> Text

   persistent	Database.Persist.TH.Internal

   Customise function for field accessors applied only when the field name matches any of Haskell keywords. Default: suffix "_".

5. setImplicitIdDef :: ImplicitIdDef -> MkPersistSettings -> MkPersistSettings

   persistent	Database.Persist.TH.Internal

   Set the ImplicitIdDef in the given MkPersistSettings. The default value is autoIncrementingInteger.

6. Divide :: PersistUpdate

   persistent	Database.Persist.Types

   No documentation available.

7. PersistInvalidField :: Text -> PersistException

   persistent	Database.Persist.Types

   No documentation available.

8. PersistObjectId :: ByteString -> PersistValue

   persistent	Database.Persist.Types

   Intended especially for MongoDB backend

9. fieldIsImplicitIdColumn :: FieldDef -> !Bool

   persistent	Database.Persist.Types

   True if the field is an implicit ID column. False otherwise.

10. isValidAbsDir :: PosixPath -> Bool

    path	OsPath.Internal.Posix

    Is the PosixPath a valid absolute dir?

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