Database.Bolt.Extras.Generic

Documentation

newtype BoltEnum a

Wrapper to encode enum-like types as strings in the DB.

Intended usage is with DerivingVia:

>>> :{
data Color = Red | Green | Blue
  deriving (Show, Generic)
  deriving (ToValue, FromValue) via BoltEnum Color
:}

>>> toValue Red
T "Red"
>>> fromValue (T "Blue") :: Color
Blue
>>> fromValue (T "Brown") :: Color
*** Exception: Could not unpack unknown value Brown of Color
...
...

Constructors

BoltEnum a

Instances

Eq a => Eq (BoltEnum a)

Defined in Database.Bolt.Extras.Generic

Methods

(==) :: BoltEnum a -> BoltEnum a -> Bool

(/=) :: BoltEnum a -> BoltEnum a -> Bool

Show a => Show (BoltEnum a)

Defined in Database.Bolt.Extras.Generic

Methods

showsPrec :: Int -> BoltEnum a -> ShowS

show :: BoltEnum a -> String

showList :: [BoltEnum a] -> ShowS

Generic (BoltEnum a)

Defined in Database.Bolt.Extras.Generic

Associated Types

type Rep (BoltEnum a) :: Type -> Type

Methods

from :: BoltEnum a -> Rep (BoltEnum a) x

to :: Rep (BoltEnum a) x -> BoltEnum a

(Typeable a, Generic a, GFromValue (Rep a)) => FromValue (BoltEnum a)

Defined in Database.Bolt.Extras.Generic

Methods

fromValue :: Value -> BoltEnum a

(Generic a, GToValue (Rep a)) => ToValue (BoltEnum a)

Defined in Database.Bolt.Extras.Generic

Methods

toValue :: BoltEnum a -> Value

type Rep (BoltEnum a)

Defined in Database.Bolt.Extras.Generic

type Rep (BoltEnum a) = D1 ('MetaData "BoltEnum" "Database.Bolt.Extras.Generic" "hasbolt-extras-0.0.1.8-5FJenUfiVLy6ZOrv0ysxyJ" 'True) (C1 ('MetaCons "BoltEnum" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 a)))

class GToValue rep where

Methods

gToValue :: rep a -> String

Instances

(GToValue l, GToValue r) => GToValue (l :+: r)

Defined in Database.Bolt.Extras.Generic

Methods

gToValue :: (l :+: r) a -> String

GToValue cs => GToValue (D1 meta cs)

Defined in Database.Bolt.Extras.Generic

Methods

gToValue :: D1 meta cs a -> String

KnownSymbol name => GToValue (C1 ('MetaCons name fixity rec) (U1 :: Type -> Type))

Defined in Database.Bolt.Extras.Generic

Methods

gToValue :: C1 ('MetaCons name fixity rec) U1 a -> String

class GFromValue rep where

Methods

gFromValue :: String -> Maybe (rep a)

Instances

(GFromValue l, GFromValue r) => GFromValue (l :+: r)

Defined in Database.Bolt.Extras.Generic

Methods

gFromValue :: String -> Maybe ((l :+: r) a)

GFromValue cs => GFromValue (D1 meta cs)

Defined in Database.Bolt.Extras.Generic

Methods

gFromValue :: String -> Maybe (D1 meta cs a)

KnownSymbol name => GFromValue (C1 ('MetaCons name fixity rec) (U1 :: Type -> Type))

Defined in Database.Bolt.Extras.Generic

Methods

gFromValue :: String -> Maybe (C1 ('MetaCons name fixity rec) U1 a)

>>> :set -XDerivingStrategies -XDerivingVia
>>> :load Database.Bolt.Extras Database.Bolt.Extras.Generic
>>> import GHC.Generics
>>> import Database.Bolt.Extras.Generic
>>> import Database.Bolt (Value (..))