Data.Tagged

Tagged values

newtype Tagged s b

A Tagged s b value is a value b with an attached phantom type s. This can be used in place of the more traditional but less safe idiom of passing in an undefined value with the type, because unlike an (s -> b), a Tagged s b can't try to use the argument s as a real value.

Moreover, you don't have to rely on the compiler to inline away the extra argument, because the newtype is "free"

Tagged has kind k -> * -> * if the compiler supports PolyKinds, therefore there is an extra k showing in the instance haddocks that may cause confusion.

Constructors

Tagged

Fields

• unTagged :: b

Instances

Bifoldable (Tagged :: TYPE LiftedRep -> Type -> Type)

Defined in Data.Tagged

Methods

bifold :: Monoid m => Tagged m m -> m

bifoldMap :: Monoid m => (a -> m) -> (b -> m) -> Tagged a b -> m

bifoldr :: (a -> c -> c) -> (b -> c -> c) -> c -> Tagged a b -> c

bifoldl :: (c -> a -> c) -> (c -> b -> c) -> c -> Tagged a b -> c

Bifunctor (Tagged :: Type -> Type -> Type)

Defined in Data.Tagged

Methods

bimap :: (a -> b) -> (c -> d) -> Tagged a c -> Tagged b d

first :: (a -> b) -> Tagged a c -> Tagged b c

second :: (b -> c) -> Tagged a b -> Tagged a c

Bitraversable (Tagged :: Type -> Type -> Type)

Defined in Data.Tagged

Methods

bitraverse :: Applicative f => (a -> f c) -> (b -> f d) -> Tagged a b -> f (Tagged c d)

Eq2 (Tagged :: Type -> Type -> Type)

Defined in Data.Tagged

Methods

liftEq2 :: (a -> b -> Bool) -> (c -> d -> Bool) -> Tagged a c -> Tagged b d -> Bool

Ord2 (Tagged :: Type -> Type -> Type)

Defined in Data.Tagged

Methods

liftCompare2 :: (a -> b -> Ordering) -> (c -> d -> Ordering) -> Tagged a c -> Tagged b d -> Ordering

Read2 (Tagged :: Type -> Type -> Type)

Defined in Data.Tagged

Methods

liftReadsPrec2 :: (Int -> ReadS a) -> ReadS [a] -> (Int -> ReadS b) -> ReadS [b] -> Int -> ReadS (Tagged a b)

liftReadList2 :: (Int -> ReadS a) -> ReadS [a] -> (Int -> ReadS b) -> ReadS [b] -> ReadS [Tagged a b]

liftReadPrec2 :: ReadPrec a -> ReadPrec [a] -> ReadPrec b -> ReadPrec [b] -> ReadPrec (Tagged a b)

liftReadListPrec2 :: ReadPrec a -> ReadPrec [a] -> ReadPrec b -> ReadPrec [b] -> ReadPrec [Tagged a b]

Show2 (Tagged :: TYPE LiftedRep -> Type -> Type)

Defined in Data.Tagged

Methods

liftShowsPrec2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> (Int -> b -> ShowS) -> ([b] -> ShowS) -> Int -> Tagged a b -> ShowS

liftShowList2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> (Int -> b -> ShowS) -> ([b] -> ShowS) -> [Tagged a b] -> ShowS

Generic1 (Tagged s :: Type -> Type)

Defined in Data.Tagged

Associated Types

type Rep1 (Tagged s) :: k -> Type

Methods

from1 :: forall (a :: k). Tagged s a -> Rep1 (Tagged s) a

to1 :: forall (a :: k). Rep1 (Tagged s) a -> Tagged s a

Foldable (Tagged s)

Defined in Data.Tagged

Methods

fold :: Monoid m => Tagged s m -> m

foldMap :: Monoid m => (a -> m) -> Tagged s a -> m

foldMap' :: Monoid m => (a -> m) -> Tagged s a -> m

foldr :: (a -> b -> b) -> b -> Tagged s a -> b

foldr' :: (a -> b -> b) -> b -> Tagged s a -> b

foldl :: (b -> a -> b) -> b -> Tagged s a -> b

foldl' :: (b -> a -> b) -> b -> Tagged s a -> b

foldr1 :: (a -> a -> a) -> Tagged s a -> a

foldl1 :: (a -> a -> a) -> Tagged s a -> a

toList :: Tagged s a -> [a]

null :: Tagged s a -> Bool

length :: Tagged s a -> Int

elem :: Eq a => a -> Tagged s a -> Bool

maximum :: Ord a => Tagged s a -> a

minimum :: Ord a => Tagged s a -> a

sum :: Num a => Tagged s a -> a

product :: Num a => Tagged s a -> a

Eq1 (Tagged s)

Defined in Data.Tagged

Methods

liftEq :: (a -> b -> Bool) -> Tagged s a -> Tagged s b -> Bool

Ord1 (Tagged s)

Defined in Data.Tagged

Methods

liftCompare :: (a -> b -> Ordering) -> Tagged s a -> Tagged s b -> Ordering

Read1 (Tagged s)

Defined in Data.Tagged

Methods

liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (Tagged s a)

liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [Tagged s a]

liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (Tagged s a)

liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [Tagged s a]

Show1 (Tagged s)

Defined in Data.Tagged

Methods

liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> Tagged s a -> ShowS

liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [Tagged s a] -> ShowS

Traversable (Tagged s)

Defined in Data.Tagged

Methods

traverse :: Applicative f => (a -> f b) -> Tagged s a -> f (Tagged s b)

sequenceA :: Applicative f => Tagged s (f a) -> f (Tagged s a)

mapM :: Monad m => (a -> m b) -> Tagged s a -> m (Tagged s b)

sequence :: Monad m => Tagged s (m a) -> m (Tagged s a)

Applicative (Tagged s)

Defined in Data.Tagged

Methods

pure :: a -> Tagged s a

(<*>) :: Tagged s (a -> b) -> Tagged s a -> Tagged s b

liftA2 :: (a -> b -> c) -> Tagged s a -> Tagged s b -> Tagged s c

(*>) :: Tagged s a -> Tagged s b -> Tagged s b

(<*) :: Tagged s a -> Tagged s b -> Tagged s a

Functor (Tagged s)

Defined in Data.Tagged

Methods

fmap :: (a -> b) -> Tagged s a -> Tagged s b

(<$) :: a -> Tagged s b -> Tagged s a

Monad (Tagged s)

Defined in Data.Tagged

Methods

(>>=) :: Tagged s a -> (a -> Tagged s b) -> Tagged s b

(>>) :: Tagged s a -> Tagged s b -> Tagged s b

return :: a -> Tagged s a

(Data s, Data b) => Data (Tagged s b)

Defined in Data.Tagged

Methods

gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> Tagged s b -> c (Tagged s b)

gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Tagged s b)

toConstr :: Tagged s b -> Constr

dataTypeOf :: Tagged s b -> DataType

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Tagged s b))

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Tagged s b))

gmapT :: (forall b0. Data b0 => b0 -> b0) -> Tagged s b -> Tagged s b

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Tagged s b -> r

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Tagged s b -> r

gmapQ :: (forall d. Data d => d -> u) -> Tagged s b -> [u]

gmapQi :: Int -> (forall d. Data d => d -> u) -> Tagged s b -> u

gmapM :: Monad m => (forall d. Data d => d -> m d) -> Tagged s b -> m (Tagged s b)

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Tagged s b -> m (Tagged s b)

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Tagged s b -> m (Tagged s b)

IsString a => IsString (Tagged s a)

Defined in Data.Tagged

Methods

fromString :: String -> Tagged s a

Storable a => Storable (Tagged s a)

Defined in Data.Tagged

Methods

sizeOf :: Tagged s a -> Int

alignment :: Tagged s a -> Int

peekElemOff :: Ptr (Tagged s a) -> Int -> IO (Tagged s a)

pokeElemOff :: Ptr (Tagged s a) -> Int -> Tagged s a -> IO ()

peekByteOff :: Ptr b -> Int -> IO (Tagged s a)

pokeByteOff :: Ptr b -> Int -> Tagged s a -> IO ()

peek :: Ptr (Tagged s a) -> IO (Tagged s a)

poke :: Ptr (Tagged s a) -> Tagged s a -> IO ()

(Semigroup a, Monoid a) => Monoid (Tagged s a)

Defined in Data.Tagged

Methods

mempty :: Tagged s a

mappend :: Tagged s a -> Tagged s a -> Tagged s a

mconcat :: [Tagged s a] -> Tagged s a

Semigroup a => Semigroup (Tagged s a)

Defined in Data.Tagged

Methods

(<>) :: Tagged s a -> Tagged s a -> Tagged s a

sconcat :: NonEmpty (Tagged s a) -> Tagged s a

stimes :: Integral b => b -> Tagged s a -> Tagged s a

Bits a => Bits (Tagged s a)

Defined in Data.Tagged

Methods

(.&.) :: Tagged s a -> Tagged s a -> Tagged s a

(.|.) :: Tagged s a -> Tagged s a -> Tagged s a

xor :: Tagged s a -> Tagged s a -> Tagged s a

complement :: Tagged s a -> Tagged s a

shift :: Tagged s a -> Int -> Tagged s a

rotate :: Tagged s a -> Int -> Tagged s a

zeroBits :: Tagged s a

bit :: Int -> Tagged s a

setBit :: Tagged s a -> Int -> Tagged s a

clearBit :: Tagged s a -> Int -> Tagged s a

complementBit :: Tagged s a -> Int -> Tagged s a

testBit :: Tagged s a -> Int -> Bool

bitSizeMaybe :: Tagged s a -> Maybe Int

bitSize :: Tagged s a -> Int

isSigned :: Tagged s a -> Bool

shiftL :: Tagged s a -> Int -> Tagged s a

unsafeShiftL :: Tagged s a -> Int -> Tagged s a

shiftR :: Tagged s a -> Int -> Tagged s a

unsafeShiftR :: Tagged s a -> Int -> Tagged s a

rotateL :: Tagged s a -> Int -> Tagged s a

rotateR :: Tagged s a -> Int -> Tagged s a

popCount :: Tagged s a -> Int

FiniteBits a => FiniteBits (Tagged s a)

Defined in Data.Tagged

Methods

finiteBitSize :: Tagged s a -> Int

countLeadingZeros :: Tagged s a -> Int

countTrailingZeros :: Tagged s a -> Int

Bounded b => Bounded (Tagged s b)

Defined in Data.Tagged

Methods

minBound :: Tagged s b

maxBound :: Tagged s b

Enum a => Enum (Tagged s a)

Defined in Data.Tagged

Methods

succ :: Tagged s a -> Tagged s a

pred :: Tagged s a -> Tagged s a

toEnum :: Int -> Tagged s a

fromEnum :: Tagged s a -> Int

enumFrom :: Tagged s a -> [Tagged s a]

enumFromThen :: Tagged s a -> Tagged s a -> [Tagged s a]

enumFromTo :: Tagged s a -> Tagged s a -> [Tagged s a]

enumFromThenTo :: Tagged s a -> Tagged s a -> Tagged s a -> [Tagged s a]

Floating a => Floating (Tagged s a)

Defined in Data.Tagged

Methods

pi :: Tagged s a

exp :: Tagged s a -> Tagged s a

log :: Tagged s a -> Tagged s a

sqrt :: Tagged s a -> Tagged s a

(**) :: Tagged s a -> Tagged s a -> Tagged s a

logBase :: Tagged s a -> Tagged s a -> Tagged s a

sin :: Tagged s a -> Tagged s a

cos :: Tagged s a -> Tagged s a

tan :: Tagged s a -> Tagged s a

asin :: Tagged s a -> Tagged s a

acos :: Tagged s a -> Tagged s a

atan :: Tagged s a -> Tagged s a

sinh :: Tagged s a -> Tagged s a

cosh :: Tagged s a -> Tagged s a

tanh :: Tagged s a -> Tagged s a

asinh :: Tagged s a -> Tagged s a

acosh :: Tagged s a -> Tagged s a

atanh :: Tagged s a -> Tagged s a

log1p :: Tagged s a -> Tagged s a

expm1 :: Tagged s a -> Tagged s a

log1pexp :: Tagged s a -> Tagged s a

log1mexp :: Tagged s a -> Tagged s a

RealFloat a => RealFloat (Tagged s a)

Defined in Data.Tagged

Methods

floatRadix :: Tagged s a -> Integer

floatDigits :: Tagged s a -> Int

floatRange :: Tagged s a -> (Int, Int)

decodeFloat :: Tagged s a -> (Integer, Int)

encodeFloat :: Integer -> Int -> Tagged s a

exponent :: Tagged s a -> Int

significand :: Tagged s a -> Tagged s a

scaleFloat :: Int -> Tagged s a -> Tagged s a

isNaN :: Tagged s a -> Bool

isInfinite :: Tagged s a -> Bool

isDenormalized :: Tagged s a -> Bool

isNegativeZero :: Tagged s a -> Bool

isIEEE :: Tagged s a -> Bool

atan2 :: Tagged s a -> Tagged s a -> Tagged s a

Generic (Tagged s b)

Defined in Data.Tagged

Associated Types

type Rep (Tagged s b) :: Type -> Type

Methods

from :: Tagged s b -> Rep (Tagged s b) x

to :: Rep (Tagged s b) x -> Tagged s b

Ix b => Ix (Tagged s b)

Defined in Data.Tagged

Methods

range :: (Tagged s b, Tagged s b) -> [Tagged s b]

index :: (Tagged s b, Tagged s b) -> Tagged s b -> Int

unsafeIndex :: (Tagged s b, Tagged s b) -> Tagged s b -> Int

inRange :: (Tagged s b, Tagged s b) -> Tagged s b -> Bool

rangeSize :: (Tagged s b, Tagged s b) -> Int

unsafeRangeSize :: (Tagged s b, Tagged s b) -> Int

Num a => Num (Tagged s a)

Defined in Data.Tagged

Methods

(+) :: Tagged s a -> Tagged s a -> Tagged s a

(-) :: Tagged s a -> Tagged s a -> Tagged s a

(*) :: Tagged s a -> Tagged s a -> Tagged s a

negate :: Tagged s a -> Tagged s a

abs :: Tagged s a -> Tagged s a

signum :: Tagged s a -> Tagged s a

fromInteger :: Integer -> Tagged s a

Read b => Read (Tagged s b)

Defined in Data.Tagged

Methods

readsPrec :: Int -> ReadS (Tagged s b)

readList :: ReadS [Tagged s b]

readPrec :: ReadPrec (Tagged s b)

readListPrec :: ReadPrec [Tagged s b]

Fractional a => Fractional (Tagged s a)

Defined in Data.Tagged

Methods

(/) :: Tagged s a -> Tagged s a -> Tagged s a

recip :: Tagged s a -> Tagged s a

fromRational :: Rational -> Tagged s a

Integral a => Integral (Tagged s a)

Defined in Data.Tagged

Methods

quot :: Tagged s a -> Tagged s a -> Tagged s a

rem :: Tagged s a -> Tagged s a -> Tagged s a

div :: Tagged s a -> Tagged s a -> Tagged s a

mod :: Tagged s a -> Tagged s a -> Tagged s a

quotRem :: Tagged s a -> Tagged s a -> (Tagged s a, Tagged s a)

divMod :: Tagged s a -> Tagged s a -> (Tagged s a, Tagged s a)

toInteger :: Tagged s a -> Integer

Real a => Real (Tagged s a)

Defined in Data.Tagged

Methods

toRational :: Tagged s a -> Rational

RealFrac a => RealFrac (Tagged s a)

Defined in Data.Tagged

Methods

properFraction :: Integral b => Tagged s a -> (b, Tagged s a)

truncate :: Integral b => Tagged s a -> b

round :: Integral b => Tagged s a -> b

ceiling :: Integral b => Tagged s a -> b

floor :: Integral b => Tagged s a -> b

Show b => Show (Tagged s b)

Defined in Data.Tagged

Methods

showsPrec :: Int -> Tagged s b -> ShowS

show :: Tagged s b -> String

showList :: [Tagged s b] -> ShowS

NFData b => NFData (Tagged s b)

Defined in Data.Tagged

Methods

rnf :: Tagged s b -> ()

Eq b => Eq (Tagged s b)

Defined in Data.Tagged

Methods

(==) :: Tagged s b -> Tagged s b -> Bool

(/=) :: Tagged s b -> Tagged s b -> Bool

Ord b => Ord (Tagged s b)

Defined in Data.Tagged

Methods

compare :: Tagged s b -> Tagged s b -> Ordering

(<) :: Tagged s b -> Tagged s b -> Bool

(<=) :: Tagged s b -> Tagged s b -> Bool

(>) :: Tagged s b -> Tagged s b -> Bool

(>=) :: Tagged s b -> Tagged s b -> Bool

max :: Tagged s b -> Tagged s b -> Tagged s b

min :: Tagged s b -> Tagged s b -> Tagged s b

type Rep1 (Tagged s :: Type -> Type)

Defined in Data.Tagged

type Rep1 (Tagged s :: Type -> Type) = D1 ('MetaData "Tagged" "Data.Tagged" "tagged-0.8.8-D9s63x51vSh3cVaEBmve02" 'True) (C1 ('MetaCons "Tagged" 'PrefixI 'True) (S1 ('MetaSel ('Just "unTagged") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) Par1))

type Rep (Tagged s b)

Defined in Data.Tagged

type Rep (Tagged s b) = D1 ('MetaData "Tagged" "Data.Tagged" "tagged-0.8.8-D9s63x51vSh3cVaEBmve02" 'True) (C1 ('MetaCons "Tagged" 'PrefixI 'True) (S1 ('MetaSel ('Just "unTagged") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 b)))

retag :: Tagged s b -> Tagged t b

Some times you need to change the tag you have lying around. Idiomatic usage is to make a new combinator for the relationship between the tags that you want to enforce, and define that combinator using retag.

data Succ n
retagSucc :: Tagged n a -> Tagged (Succ n) a
retagSucc = retag

untag :: Tagged s b -> b

Alias for unTagged

tagSelf :: a -> Tagged a a

Tag a value with its own type.

untagSelf :: Tagged a a -> a

untagSelf is a type-restricted version of untag.

asTaggedTypeOf :: s -> tagged s b -> s

asTaggedTypeOf is a type-restricted version of const. It is usually used as an infix operator, and its typing forces its first argument (which is usually overloaded) to have the same type as the tag of the second.

witness :: Tagged a b -> a -> b

Conversion

proxy :: Tagged s a -> proxy s -> a

Convert from a Tagged representation to a representation based on a Proxy.

unproxy :: (Proxy s -> a) -> Tagged s a

Convert from a representation based on a Proxy to a Tagged representation.

tagWith :: proxy s -> a -> Tagged s a

Another way to convert a proxy to a tag.

Proxy methods GHC dropped

reproxy :: proxy a -> Proxy b

Some times you need to change the proxy you have lying around. Idiomatic usage is to make a new combinator for the relationship between the proxies that you want to enforce, and define that combinator using reproxy.

data Succ n
reproxySucc :: proxy n -> Proxy (Succ n)
reproxySucc = reproxy