-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Type-safe, non-relational, multi-backend persistence.
--   
--   This library provides just the general interface and helper functions.
--   You must use a specific backend in order to make this useful.
@package persistent-template
@version 2.0.1


-- | This module provides utilities for creating backends. Regular users do
--   not need to use this module.
module Database.Persist.TH

-- | Converts a quasi-quoted syntax into a list of entity definitions, to
--   be used as input to the template haskell generation code (mkPersist).
persistWith :: PersistSettings -> QuasiQuoter

-- | Apply <a>persistWith</a> to <a>upperCaseSettings</a>.
persistUpperCase :: QuasiQuoter

-- | Apply <a>persistWith</a> to <a>lowerCaseSettings</a>.
persistLowerCase :: QuasiQuoter

-- | Same as <a>persistWith</a>, but uses an external file instead of a
--   quasiquotation.
persistFileWith :: PersistSettings -> FilePath -> Q Exp

-- | Create data types and appropriate <a>PersistEntity</a> instances for
--   the given <a>EntityDef</a>s. Works well with the persist quasi-quoter.
mkPersist :: MkPersistSettings -> [EntityDef] -> Q [Dec]

-- | Settings to be passed to the <a>mkPersist</a> function.
data MkPersistSettings

-- | Which database backend we're using.
--   
--   When generating data types, each type is given a generic version-
--   which works with any backend- and a type synonym for the commonly used
--   backend. This is where you specify that commonly used backend.
mpsBackend :: MkPersistSettings -> Type

-- | Create generic types that can be used with multiple backends. Good for
--   reusable code, but makes error messages harder to understand. Default:
--   True.
mpsGeneric :: MkPersistSettings -> Bool

-- | Prefix field names with the model name. Default: True.
mpsPrefixFields :: MkPersistSettings -> Bool

-- | Generate <tt>ToJSON</tt>/<tt>FromJSON</tt> instances for each model
--   types. If it's <tt>Nothing</tt>, no instances will be generated.
--   Default:
--   
--   <pre>
--   Just EntityJSON
--       { entityToJSON = 'keyValueEntityToJSON
--       , entityFromJSON = 'keyValueEntityFromJSON
--       }
--   </pre>
mpsEntityJSON :: MkPersistSettings -> Maybe EntityJSON

-- | Instead of generating normal field accessors, generator lens-style
--   accessors.
--   
--   Default: False
--   
--   Since 1.3.1
mpsGenerateLenses :: MkPersistSettings -> Bool
data EntityJSON
EntityJSON :: Name -> Name -> EntityJSON

-- | Name of the <tt>toJSON</tt> implementation for <tt>Entity a</tt>.
entityToJSON :: EntityJSON -> Name

-- | Name of the <tt>fromJSON</tt> implementation for <tt>Entity a</tt>.
entityFromJSON :: EntityJSON -> Name

-- | Create an <tt>MkPersistSettings</tt> with default values.
mkPersistSettings :: Type -> MkPersistSettings

-- | Use the <tt>SqlPersist</tt> backend.
sqlSettings :: MkPersistSettings

-- | Same as <a>sqlSettings</a>.
--   
--   Since 1.1.1

-- | <i>Deprecated: use sqlSettings </i>
sqlOnlySettings :: MkPersistSettings

-- | Creates a single function to perform all migrations for the entities
--   defined here. One thing to be aware of is dependencies: if you have
--   entities with foreign references, make sure to place those definitions
--   after the entities they reference.
mkMigrate :: String -> [EntityDef] -> Q [Dec]

-- | Save the <tt>EntityDef</tt>s passed in under the given name.
mkSave :: String -> [EntityDef] -> Q [Dec]

-- | Generate a <a>DeleteCascade</a> instance for the given
--   <tt>EntityDef</tt>s.
mkDeleteCascade :: MkPersistSettings -> [EntityDef] -> Q [Dec]

-- | Apply the given list of functions to the same <tt>EntityDef</tt>s.
--   
--   This function is useful for cases such as:
--   
--   <pre>
--   &gt;&gt;&gt; share [mkSave "myDefs", mkPersist sqlSettings] [persistLowerCase|...|]
--   </pre>
share :: [[EntityDef] -> Q [Dec]] -> [EntityDef] -> Q [Dec]

-- | Automatically creates a valid <a>PersistField</a> instance for any
--   datatype that has valid <a>Show</a> and <a>Read</a> instances. Can be
--   very convenient for <a>Enum</a> types.
derivePersistField :: String -> Q [Dec]

-- | Automatically creates a valid <a>PersistField</a> instance for any
--   datatype that has valid <a>ToJSON</a> and <a>FromJSON</a> instances.
--   For a datatype <tt>T</tt> it generates instances similar to these:
--   
--   <pre>
--   instance PersistField T where
--       toPersistValue = PersistByteString . L.toStrict . encode
--       fromPersistValue = (left T.pack) . eitherDecodeStrict' &lt;=&lt; fromPersistValue
--   instance PersistFieldSql T where
--       sqlType _ = SqlString
--   </pre>
derivePersistFieldJSON :: String -> Q [Dec]

-- | produce code similar to the following:
--   
--   <pre>
--   instance PersistEntity e =&gt; PersistField e where
--      toPersistValue = PersistMap $ zip columNames (map toPersistValue . toPersistFields)
--      fromPersistValue (PersistMap o) = 
--          let columns = HM.fromList o
--          in fromPersistValues $ map (name -&gt;
--            case HM.lookup name columns of
--              Just v -&gt; v
--              Nothing -&gt; PersistNull
--      fromPersistValue x = Left $ <a>Expected PersistMap, received: </a> ++ show x
--      sqlType _ = SqlString
--   </pre>
persistFieldFromEntity :: MkPersistSettings -> EntityDef -> Q [Dec]
packPTH :: String -> Text
lensPTH :: (s -> a) -> (s -> b -> t) -> Lens s t a b
instance Show SqlTypeExp
instance Show EntityDefSqlTypeExp
instance Lift SqlType
instance Lift PersistUpdate
instance Lift PersistFilter
instance Lift FieldType
instance Lift DBName
instance Lift HaskellName
instance (Lift' k, Lift' v) => Lift' (Map k v)
instance Lift' a => Lift' [a]
instance Lift' Text
instance Lift' SqlTypeExp
instance Lift' ()
instance Lift' EntityDef
instance Lift' a => Lift' (Maybe a)
instance Lift' SqlType
instance Lift ForeignDef
instance Lift PrimaryDef
instance Lift UniqueDef
instance Lift FieldDef
instance Lift EntityDef
instance Lift EmbedFieldDef
instance Lift EmbedEntityDef
instance Lift ReferenceDef
instance Lift EntityDefSqlTypeExp
instance Lift FieldSqlTypeExp
instance Lift FieldsSqlTypeExp
instance Lift SqlTypeExp