libghc-persistent-template-doc 2.1.4-1build1 / usr / share / doc / libghc-persistent-template-doc / html / persistent-template.txt

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


-- | Type-safe, non-relational, multi-backend persistence.
--   
--   Hackage documentation generation is not reliable. For up to date
--   documentation, please see:
--   <a>http://www.stackage.org/package/persistent-template</a>.
@package persistent-template
@version 2.1.4


-- | 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 $ "Expected PersistMap, received: " ++ 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 GHC.Show.Show Database.Persist.TH.FTTypeConDescr
instance GHC.Show.Show Database.Persist.TH.EntityDefSqlTypeExp
instance GHC.Show.Show Database.Persist.TH.SqlTypeExp
instance Language.Haskell.TH.Syntax.Lift Database.Persist.TH.SqlTypeExp
instance Language.Haskell.TH.Syntax.Lift Database.Persist.TH.FieldsSqlTypeExp
instance Language.Haskell.TH.Syntax.Lift Database.Persist.TH.FieldSqlTypeExp
instance Language.Haskell.TH.Syntax.Lift Database.Persist.TH.EntityDefSqlTypeExp
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.ReferenceDef
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.EmbedEntityDef
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.EmbedFieldDef
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.EntityDef
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.FieldDef
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.UniqueDef
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.CompositeDef
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.ForeignDef
instance Database.Persist.TH.Lift' Data.Text.Internal.Text
instance Database.Persist.TH.Lift' a => Database.Persist.TH.Lift' [a]
instance (Database.Persist.TH.Lift' k, Database.Persist.TH.Lift' v) => Database.Persist.TH.Lift' (Data.Map.Base.Map k v)
instance Database.Persist.TH.Lift' a => Language.Haskell.TH.Syntax.Lift a
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.HaskellName
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.DBName
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.FieldType
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.PersistFilter
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.PersistUpdate
instance Language.Haskell.TH.Syntax.Lift Database.Persist.Types.Base.SqlType