diff --git a/src/lib/Witch.hs b/src/lib/Witch.hs
--- a/src/lib/Witch.hs
+++ b/src/lib/Witch.hs
@@ -184,11 +184,36 @@
   -- - You should not have both a @From@ instance and a @TryFrom@ instance for
   --   the same pair of types.
   --
+  -- - If you have a @From@ or @TryFrom@ instance for a pair of types, then
+  --   you should probably have a @From@ or @TryFrom@ instance for the same
+  --   pair of types but in the opposite direction. In other words if you have
+  --   @From a b@ then you should have @From b a@ or @TryFrom b a@.
+  --
   -- In general if @s@ /is/ a @t@, then you should add a 'Witch.From.From'
   -- instance for it. But if @s@ merely /can be/ a @t@, then you could add a
   -- 'Witch.TryFrom.TryFrom' instance for it. And if it is technically
   -- possible to convert from @s@ to @t@ but there are a lot of caveats, you
   -- probably should not write any instances at all.
+
+  -- ** Laws
+  -- | As the previous section notes, there aren't any cut and dried laws for
+  -- the @From@ and @TryFrom@ type classes. However it can be useful to
+  -- consider the following equations for guiding instances:
+  --
+  -- > -- same strictness
+  -- > seq (from @a @b x) y = seq x y
+  -- > seq (tryFrom @a @b x) y = seq x y
+  --
+  -- > -- round trip
+  -- > from @b @a (from @a @b x) = x
+  --
+  -- > -- transitive
+  -- > from @b @c (from @a @b x) = from @a @c x
+  -- > tryFrom @b @a (from @a @b x) = Right x
+  -- > if isRight (tryFrom @a @b x) then
+  -- >   fmap (from @b @a) (tryFrom @a @b x) = Right x
+  -- > if isRight (tryFrom @a @b x) then do
+  -- >   fmap (tryFrom @b @a) (tryFrom @a @b x) = Right (Right x)
 
   -- ** Integral types
   -- | There are a lot of types that represent various different ranges of
diff --git a/src/lib/Witch/Instances.hs b/src/lib/Witch/Instances.hs
--- a/src/lib/Witch/Instances.hs
+++ b/src/lib/Witch/Instances.hs
@@ -17,6 +17,7 @@
 import qualified Data.Int as Int
 import qualified Data.IntMap as IntMap
 import qualified Data.IntSet as IntSet
+import qualified Data.List as List
 import qualified Data.List.NonEmpty as NonEmpty
 import qualified Data.Map as Map
 import qualified Data.Ratio as Ratio
@@ -32,6 +33,7 @@
 import qualified Data.Time.Clock.TAI as Time
 import qualified Data.Word as Word
 import qualified GHC.Float as Float
+import qualified Numeric
 import qualified Numeric.Natural as Natural
 import qualified Witch.From as From
 import qualified Witch.TryFrom as TryFrom
@@ -256,7 +258,8 @@
   -- This should use @eitherTryFrom fromNonNegativeIntegral@, but that causes
   -- a bug in GHC 9.0.1.
   -- https://mail.haskell.org/pipermail/haskell-cafe/2021-March/133540.html
-  tryFrom = Utility.eitherTryFrom $ \ s -> TryFrom.tryFrom (From.from s :: Integer)
+  tryFrom =
+    Utility.eitherTryFrom $ \s -> TryFrom.tryFrom (From.from s :: Integer)
 
 -- | Uses 'fromIntegral' when the input is between -16,777,215 and 16,777,215
 -- inclusive.
@@ -631,9 +634,8 @@
 -- | Uses 'fromIntegral' when the input is less than or equal to
 -- 9,007,199,254,740,991.
 instance TryFrom.TryFrom Word.Word64 Double where
-  tryFrom = Utility.eitherTryFrom $ \s -> if s <= maxDouble
-    then Right $ fromIntegral s
-    else Left Exception.Overflow
+  tryFrom = Utility.eitherTryFrom $ \s ->
+    if s <= maxDouble then Right $ fromIntegral s else Left Exception.Overflow
 
 -- Word
 
@@ -748,9 +750,8 @@
 -- | Uses 'fromIntegral' when the input is less than or equal to
 -- 9,007,199,254,740,991.
 instance TryFrom.TryFrom Natural.Natural Double where
-  tryFrom = Utility.eitherTryFrom $ \s -> if s <= maxDouble
-    then Right $ fromIntegral s
-    else Left Exception.Overflow
+  tryFrom = Utility.eitherTryFrom $ \s ->
+    if s <= maxDouble then Right $ fromIntegral s else Left Exception.Overflow
 
 -- Float
 
@@ -808,13 +809,9 @@
 instance TryFrom.TryFrom Float Natural.Natural where
   tryFrom = Utility.tryVia @Integer
 
--- | Uses 'toRational' when the input is not NaN or infinity.
+-- | Uses 'Numeric.floatToDigits' when the input is not NaN or infinity.
 instance TryFrom.TryFrom Float Rational where
-  tryFrom = Utility.eitherTryFrom $ \s -> if isNaN s
-    then Left Exception.LossOfPrecision
-    else if isInfinite s
-      then if s > 0 then Left Exception.Overflow else Left Exception.Underflow
-      else Right $ toRational s
+  tryFrom = Utility.eitherTryFrom realFloatToRational
 
 -- | Uses 'Float.float2Double'.
 instance From.From Float Double where
@@ -876,13 +873,9 @@
 instance TryFrom.TryFrom Double Natural.Natural where
   tryFrom = Utility.tryVia @Integer
 
--- | Uses 'toRational' when the input is not NaN or infinity.
+-- | Uses 'Numeric.floatToDigits' when the input is not NaN or infinity.
 instance TryFrom.TryFrom Double Rational where
-  tryFrom = Utility.eitherTryFrom $ \s -> if isNaN s
-    then Left Exception.LossOfPrecision
-    else if isInfinite s
-      then if s > 0 then Left Exception.Overflow else Left Exception.Underflow
-      else Right $ toRational s
+  tryFrom = Utility.eitherTryFrom realFloatToRational
 
 -- | Uses 'Float.double2Float'. This necessarily loses some precision.
 instance From.From Double Float where
@@ -914,9 +907,7 @@
     let
       t :: Fixed.Fixed a
       t = fromRational s
-    in if toRational t == s
-      then Right t
-      else Left Exception.LossOfPrecision
+    in if toRational t == s then Right t else Left Exception.LossOfPrecision
 
 -- Fixed
 
@@ -1032,11 +1023,17 @@
 
 -- | Converts via 'Text.Text'.
 instance TryFrom.TryFrom ByteString.ByteString LazyText.Text where
-  tryFrom = Utility.eitherTryFrom $ fmap (Utility.into @LazyText.Text) . Utility.tryInto @Text.Text
+  tryFrom =
+    Utility.eitherTryFrom
+      $ fmap (Utility.into @LazyText.Text)
+      . Utility.tryInto @Text.Text
 
 -- | Converts via 'Text.Text'.
 instance TryFrom.TryFrom ByteString.ByteString String where
-  tryFrom = Utility.eitherTryFrom $ fmap (Utility.into @String) . Utility.tryInto @Text.Text
+  tryFrom =
+    Utility.eitherTryFrom
+      $ fmap (Utility.into @String)
+      . Utility.tryInto @Text.Text
 
 -- LazyByteString
 
@@ -1058,11 +1055,17 @@
 
 -- | Converts via 'LazyText.Text'.
 instance TryFrom.TryFrom LazyByteString.ByteString Text.Text where
-  tryFrom = Utility.eitherTryFrom $ fmap (Utility.into @Text.Text) . Utility.tryInto @LazyText.Text
+  tryFrom =
+    Utility.eitherTryFrom
+      $ fmap (Utility.into @Text.Text)
+      . Utility.tryInto @LazyText.Text
 
 -- | Converts via 'LazyText.Text'.
 instance TryFrom.TryFrom LazyByteString.ByteString String where
-  tryFrom = Utility.eitherTryFrom $ fmap (Utility.into @String) . Utility.tryInto @LazyText.Text
+  tryFrom =
+    Utility.eitherTryFrom
+      $ fmap (Utility.into @String)
+      . Utility.tryInto @LazyText.Text
 
 -- ShortByteString
 
@@ -1248,6 +1251,29 @@
 -- | Uses 'Time.zonedTimeToUTC'.
 instance From.From Time.ZonedTime Time.UTCTime where
   from = Time.zonedTimeToUTC
+
+--
+
+realFloatToRational
+  :: RealFloat s => s -> Either Exception.ArithException Rational
+realFloatToRational s
+  | isNaN s = Left Exception.LossOfPrecision
+  | isInfinite s = if s > 0
+    then Left Exception.Overflow
+    else Left Exception.Underflow
+  | otherwise = Right $ overPositive
+    (uncurry makeRational . uncurry fromDigits . Numeric.floatToDigits 10)
+    s
+
+overPositive :: (Eq a, Num a, Num b) => (a -> b) -> a -> b
+overPositive f x = if signum x == -1 then -(f (-x)) else f x
+
+fromDigits :: [Int] -> Int -> (Integer, Integer)
+fromDigits ds e =
+  List.foldl' (\(a, n) d -> (a * 10 + toInteger d, n - 1)) (0, toInteger e) ds
+
+makeRational :: Integer -> Integer -> Rational
+makeRational d e = toRational d * 10 ^^ e
 
 fromNonNegativeIntegral
   :: (Integral s, Num t) => s -> Either Exception.ArithException t
diff --git a/src/lib/Witch/Utility.hs b/src/lib/Witch/Utility.hs
--- a/src/lib/Witch/Utility.hs
+++ b/src/lib/Witch/Utility.hs
@@ -29,11 +29,7 @@
 -- >
 -- > -- Prefer this:
 -- > into @t x
-into
-  :: forall target source
-   . From.From source target
-  => source
-  -> target
+into :: forall target source . From.From source target => source -> target
 into = From.from
 
 -- | This function converts from some @source@ type into some @target@ type,
@@ -48,9 +44,7 @@
 -- > over @t f
 over
   :: forall target source
-   . ( From.From source target
-     , From.From target source
-     )
+   . (From.From source target, From.From target source)
   => (target -> target)
   -> source
   -> source
@@ -68,9 +62,7 @@
 -- > via @u
 via
   :: forall through source target
-   . ( From.From source through
-     , From.From through target
-     )
+   . (From.From source through, From.From through target)
   => source
   -> target
 via = From.from . (\x -> x :: through) . From.from
@@ -105,9 +97,7 @@
 -- > tryVia @u
 tryVia
   :: forall through source target
-   . ( TryFrom.TryFrom source through
-     , TryFrom.TryFrom through target
-     )
+   . (TryFrom.TryFrom source through, TryFrom.TryFrom through target)
   => source
   -> Either (TryFromException.TryFromException source target) target
 tryVia s = case TryFrom.tryFrom s of
diff --git a/src/test/Main.hs b/src/test/Main.hs
--- a/src/test/Main.hs
+++ b/src/test/Main.hs
@@ -32,1869 +32,1889 @@
 import qualified Witch
 
 main :: IO ()
-main = runTestTTAndExit $ "Witch" ~:
-  [ "From" ~:
-    [ "from" ~:
-      [ Witch.from (1 :: Int.Int8) ~?= (1 :: Int.Int16)
-      ]
-    ]
-  , "TryFrom" ~:
-    [ "tryFrom" ~:
-      let f = hush . Witch.tryFrom @Int.Int16 @Int.Int8 in
-      [ f 1 ~?= Just 1
-      , f 128 ~?= Nothing
-      ]
-    ]
-  , "Utility" ~:
-    [ "as" ~:
-      [ Witch.as @Int.Int8 1 ~?= 1
-      ]
-    , "from" ~:
-      [ Witch.from @Int.Int8 1 ~?= (1 :: Int.Int16)
-      ]
-    , "into" ~:
-      [ Witch.into @Int.Int16 (1 :: Int.Int8) ~?= 1
-      ]
-    , "over" ~:
-      [ Witch.over @Int.Int8 (+ 1) (Age 1) ~?= Age 2
-      ]
-    , "via" ~:
-      [ Witch.via @Int.Int16 (1 :: Int.Int8) ~?= (1 :: Int.Int32)
-      ]
-    , "tryFrom" ~:
-      [ hush (Witch.tryFrom @Int.Int16 1) ~?= Just (1 :: Int.Int8)
-      ]
-    , "tryInto" ~:
-      [ hush (Witch.tryInto @Int.Int8 (1 :: Int.Int16)) ~?= Just 1
-      ]
-    , "tryVia" ~:
-      let f = Witch.tryVia @Int.Int16 @Int.Int32 @Int.Int8 in
-      [ hush (f 1) ~?= Just 1
-      , hush (f 128) ~?= Nothing
-      , hush (f 32768) ~?= Nothing
-      ]
-    , "unsafeFrom" ~:
-      let f = Witch.unsafeFrom @Int.Int16 @Int.Int8 in
-      [ f 1 ~?= 1
-      , TestCase $ do
-        result <- Exception.try @Exception.SomeException . Exception.evaluate $ f 128
-        assertBool (show result) $ Either.isLeft result
-      ]
-    , "unsafeInto" ~:
-      [ Witch.unsafeInto @Int.Int8 (1 :: Int.Int16) ~?= 1
-      ]
-    ]
-  , "Lift" ~:
-    [ "liftedFrom" ~:
-      [ ($$(Witch.liftedFrom (1 :: Int.Int16)) :: Int.Int8) ~?= 1
-      ]
-    , "liftedInto" ~:
-      [ $$(Witch.liftedInto @Int.Int8 (1 :: Int.Int16)) ~?= 1
-      ]
-    ]
-  , "TryFromException" ~:
-    [ "show" ~:
-      [ show (Witch.TryFromException @Int @Int 0 Nothing) ~?= "TryFromException @Int @Int 0 Nothing"
-      , show (Witch.TryFromException @(Seq.Seq Int) @(Seq.Seq Int) (Seq.fromList []) (Just (Exception.toException Exception.Overflow))) ~?= "TryFromException @(Seq Int) @(Seq Int) (fromList []) (Just arithmetic overflow)"
-      ]
-    ]
-  , "Instances" ~:
-    [ "From a a" ~:
-      let f = Witch.from @Int @Int in
-      [ f 0 ~?= 0
-      ]
-
-    -- Int8
-
-    , "From Int8 Int16" ~:
-      let f = Witch.from @Int.Int8 @Int.Int16 in
-      [ f 0 ~?= 0
-      , f 127 ~?= 127
-      , f (-128) ~?= (-128)
-      ]
-    , "From Int8 Int32" ~:
-      let f = Witch.from @Int.Int8 @Int.Int32 in
-      [ f 0 ~?= 0
-      , f 127 ~?= 127
-      , f (-128) ~?= (-128)
-      ]
-    , "From Int8 Int64" ~:
-      let f = Witch.from @Int.Int8 @Int.Int64 in
-      [ f 0 ~?= 0
-      , f 127 ~?= 127
-      , f (-128) ~?= (-128)
-      ]
-    , "From Int8 Int" ~:
-      let f = Witch.from @Int.Int8 @Int in
-      [ f 0 ~?= 0
-      , f 127 ~?= 127
-      , f (-128) ~?= (-128)
-      ]
-    , "From Int8 Integer" ~:
-      let f = Witch.from @Int.Int8 @Integer in
-      [ f 0 ~?= 0
-      , f 127 ~?= 127
-      , f (-128) ~?= (-128)
-      ]
-    , "TryFrom Int8 Word8" ~:
-      let f = hush . Witch.tryFrom @Int.Int8 @Word.Word8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int8 Word16" ~:
-      let f = hush . Witch.tryFrom @Int.Int8 @Word.Word16 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int8 Word32" ~:
-      let f = hush . Witch.tryFrom @Int.Int8 @Word.Word32 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int8 Word64" ~:
-      let f = hush . Witch.tryFrom @Int.Int8 @Word.Word64 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int8 Word" ~:
-      let f = hush . Witch.tryFrom @Int.Int8 @Word in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int8 Natural" ~:
-      let f = hush . Witch.tryFrom @Int.Int8 @Natural.Natural in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f (-1) ~?= Nothing
-      ]
-    , "From Int8 Float" ~:
-      let f = Witch.from @Int.Int8 @Float in
-      [ f 0 ~?= 0
-      , f 127 ~?= 127
-      , f (-128) ~?= (-128)
-      ]
-    , "From Int8 Double" ~:
-      let f = Witch.from @Int.Int8 @Double in
-      [ f 0 ~?= 0
-      , f 127 ~?= 127
-      , f (-128) ~?= (-128)
-      ]
-
-    -- Int16
-
-    , "TryFrom Int16 Int8" ~:
-      let f = hush . Witch.tryFrom @Int.Int16 @Int.Int8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f 128 ~?= Nothing
-      , f (-128) ~?= Just (-128)
-      , f (-129) ~?= Nothing
-      ]
-    , "From Int16 Int32" ~:
-      let f = Witch.from @Int.Int16 @Int.Int32 in
-      [ f 0 ~?= 0
-      , f 32767 ~?= 32767
-      , f (-32768) ~?= (-32768)
-      ]
-    , "From Int16 Int64" ~:
-      let f = Witch.from @Int.Int16 @Int.Int64 in
-      [ f 0 ~?= 0
-      , f 32767 ~?= 32767
-      , f (-32768) ~?= (-32768)
-      ]
-    , "From Int16 Int" ~:
-      let f = Witch.from @Int.Int16 @Int in
-      [ f 0 ~?= 0
-      , f 32767 ~?= 32767
-      , f (-32768) ~?= (-32768)
-      ]
-    , "From Int16 Integer" ~:
-      let f = Witch.from @Int.Int16 @Integer in
-      [ f 0 ~?= 0
-      , f 32767 ~?= 32767
-      , f (-32768) ~?= (-32768)
-      ]
-    , "TryFrom Int16 Word8" ~:
-      let f = hush . Witch.tryFrom @Int.Int16 @Word.Word8 in
-      [ f 0 ~?= Just 0
-      , f 255 ~?= Just 255
-      , f 256 ~?= Nothing
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int16 Word16" ~:
-      let f = hush . Witch.tryFrom @Int.Int16 @Word.Word16 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int16 Word32" ~:
-      let f = hush . Witch.tryFrom @Int.Int16 @Word.Word32 in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int16 Word64" ~:
-      let f = hush . Witch.tryFrom @Int.Int16 @Word.Word64 in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int16 Word" ~:
-      let f = hush . Witch.tryFrom @Int.Int16 @Word in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int16 Natural" ~:
-      let f = hush . Witch.tryFrom @Int.Int16 @Natural.Natural in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f (-1) ~?= Nothing
-      ]
-    , "From Int16 Float" ~:
-      let f = Witch.from @Int.Int16 @Float in
-      [ f 0 ~?= 0
-      , f 32767 ~?= 32767
-      , f (-32768) ~?= (-32768)
-      ]
-    , "From Int16 Double" ~:
-      let f = Witch.from @Int.Int16 @Double in
-      [ f 0 ~?= 0
-      , f 32767 ~?= 32767
-      , f (-32768) ~?= (-32768)
-      ]
-
-    -- Int32
-
-    , "TryFrom Int32 Int8" ~:
-      let f = hush . Witch.tryFrom @Int.Int32 @Int.Int8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f 128 ~?= Nothing
-      , f (-128) ~?= Just (-128)
-      , f (-129) ~?= Nothing
-      ]
-    , "TryFrom Int32 Int16" ~:
-      let f = hush . Witch.tryFrom @Int.Int32 @Int.Int16 in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f 32768 ~?= Nothing
-      , f (-32768) ~?= Just (-32768)
-      , f (-32769) ~?= Nothing
-      ]
-    , "From Int32 Int64" ~:
-      let f = Witch.from @Int.Int32 @Int.Int64 in
-      [ f 0 ~?= 0
-      , f 2147483647 ~?= 2147483647
-      , f (-2147483648) ~?= (-2147483648)
-      ]
-    , "TryFrom Int32 Int" ~:
-      let f = hush . Witch.tryFrom @Int.Int32 @Int in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , f (-2147483648) ~?= Just (-2147483648)
-      ]
-    , "From Int32 Integer" ~:
-      let f = Witch.from @Int.Int32 @Integer in
-      [ f 0 ~?= 0
-      , f 2147483647 ~?= 2147483647
-      , f (-2147483648) ~?= (-2147483648)
-      ]
-    , "TryFrom Int32 Word8" ~:
-      let f = hush . Witch.tryFrom @Int.Int32 @Word.Word8 in
-      [ f 0 ~?= Just 0
-      , f 255 ~?= Just 255
-      , f 256 ~?= Nothing
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int32 Word16" ~:
-      let f = hush . Witch.tryFrom @Int.Int32 @Word.Word16 in
-      [ f 0 ~?= Just 0
-      , f 65535 ~?= Just 65535
-      , f 65536 ~?= Nothing
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int32 Word32" ~:
-      let f = hush . Witch.tryFrom @Int.Int32 @Word.Word32 in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int32 Word64" ~:
-      let f = hush . Witch.tryFrom @Int.Int32 @Word.Word64 in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int32 Word" ~:
-      let f = hush . Witch.tryFrom @Int.Int32 @Word in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int32 Natural" ~:
-      let f = hush . Witch.tryFrom @Int.Int32 @Natural.Natural in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int32 Float" ~:
-      let f = hush . Witch.tryFrom @Int.Int32 @Float in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      , f (-16777215) ~?= Just (-16777215)
-      , f (-16777216) ~?= Nothing
-      ]
-    , "From Int32 Double" ~:
-      let f = Witch.from @Int.Int32 @Double in
-      [ f 0 ~?= 0
-      , f 2147483647 ~?= 2147483647
-      , f (-2147483648) ~?= (-2147483648)
-      ]
-
-    -- Int64
-
-    , "TryFrom Int64 Int8" ~:
-      let f = hush . Witch.tryFrom @Int.Int64 @Int.Int8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f 128 ~?= Nothing
-      , f (-128) ~?= Just (-128)
-      , f (-129) ~?= Nothing
-      ]
-    , "TryFrom Int64 Int16" ~:
-      let f = hush . Witch.tryFrom @Int.Int64 @Int.Int16 in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f 32768 ~?= Nothing
-      , f (-32768) ~?= Just (-32768)
-      , f (-32769) ~?= Nothing
-      ]
-    , "TryFrom Int64 Int32" ~:
-      let f = hush . Witch.tryFrom @Int.Int64 @Int.Int32 in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , f 2147483648 ~?= Nothing
-      , f (-2147483648) ~?= Just (-2147483648)
-      , f (-2147483649) ~?= Nothing
-      ]
-    , "TryFrom Int64 Int" ~:
-      let f = hush . Witch.tryFrom @Int.Int64 @Int in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Int in if toInteger x >= 9223372036854775807
-        then f 9223372036854775807 ~?= Just 9223372036854775807
-        else f (fromIntegral x) ~?= Just x
-      , let x = minBound :: Int in if toInteger x <= (-9223372036854775808)
-        then f (-9223372036854775808) ~?= Just (-9223372036854775808)
-        else f (fromIntegral x) ~?= Just x
-      ]
-    , "From Int64 Integer" ~:
-      let f = Witch.from @Int.Int64 @Integer in
-      [ f 0 ~?= 0
-      , f 9223372036854775807 ~?= 9223372036854775807
-      , f (-9223372036854775808) ~?= (-9223372036854775808)
-      ]
-    , "TryFrom Int64 Word8" ~:
-      let f = hush . Witch.tryFrom @Int.Int64 @Word.Word8 in
-      [ f 0 ~?= Just 0
-      , f 255 ~?= Just 255
-      , f 256 ~?= Nothing
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int64 Word16" ~:
-      let f = hush . Witch.tryFrom @Int.Int64 @Word.Word16 in
-      [ f 0 ~?= Just 0
-      , f 65535 ~?= Just 65535
-      , f 65536 ~?= Nothing
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int64 Word32" ~:
-      let f = hush . Witch.tryFrom @Int.Int64 @Word.Word32 in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int64 Word64" ~:
-      let f = hush . Witch.tryFrom @Int.Int64 @Word.Word64 in
-      [ f 0 ~?= Just 0
-      , f 9223372036854775807 ~?= Just 9223372036854775807
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int64 Word" ~:
-      let f = hush . Witch.tryFrom @Int.Int64 @Word in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Word in if toInteger x >= 9223372036854775807
-        then f 9223372036854775807 ~?= Just 9223372036854775807
-        else f (fromIntegral x) ~?= Just x
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int64 Natural" ~:
-      let f = hush . Witch.tryFrom @Int.Int64 @Natural.Natural in
-      [ f 0 ~?= Just 0
-      , f 9223372036854775807 ~?= Just 9223372036854775807
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int64 Float" ~:
-      let f = hush . Witch.tryFrom @Int.Int64 @Float in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      , f (-16777215) ~?= Just (-16777215)
-      , f (-16777216) ~?= Nothing
-      ]
-    , "TryFrom Int64 Double" ~:
-      let f = hush . Witch.tryFrom @Int.Int64 @Double in
-      [ f 0 ~?= Just 0
-      , f 9007199254740991 ~?= Just 9007199254740991
-      , f 9007199254740992 ~?= Nothing
-      , f (-9007199254740991) ~?= Just (-9007199254740991)
-      , f (-9007199254740992) ~?= Nothing
-      ]
-
-    -- Int
-
-    , "TryFrom Int Int8" ~:
-      let f = hush . Witch.tryFrom @Int @Int.Int8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f 128 ~?= Nothing
-      , f (-128) ~?= Just (-128)
-      , f (-129) ~?= Nothing
-      ]
-    , "TryFrom Int Int16" ~:
-      let f = hush . Witch.tryFrom @Int @Int.Int16 in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f 32768 ~?= Nothing
-      , f (-32768) ~?= Just (-32768)
-      , f (-32769) ~?= Nothing
-      ]
-    , "TryFrom Int Int32" ~:
-      let f = hush . Witch.tryFrom @Int @Int.Int32 in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , let x = maxBound :: Int in if toInteger x >= 2147483648
-        then f 2147483648 ~?= Nothing
-        else f x ~?= Just (fromIntegral x)
-      , f (-2147483648) ~?= Just (-2147483648)
-      , let x = minBound :: Int in if toInteger x <= (-2147483649)
-        then f (-2147483649) ~?= Nothing
-        else f x ~?= Just (fromIntegral x)
-      ]
-    , "From Int Int64" ~:
-      let f = Witch.from @Int @Int.Int64 in
-      [ f 0 ~?= 0
-      , f maxBound ~?= fromIntegral (maxBound :: Int)
-      , f minBound ~?= fromIntegral (minBound :: Int)
-      ]
-    , "From Int Integer" ~:
-      let f = Witch.from @Int @Integer in
-      [ f 0 ~?= 0
-      , f maxBound ~?= fromIntegral (maxBound :: Int)
-      , f minBound ~?= fromIntegral (minBound :: Int)
-      ]
-    , "TryFrom Int Word8" ~:
-      let f = hush . Witch.tryFrom @Int @Word.Word8 in
-      [ f 0 ~?= Just 0
-      , f 255 ~?= Just 255
-      , f 256 ~?= Nothing
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int Word16" ~:
-      let f = hush . Witch.tryFrom @Int @Word.Word16 in
-      [ f 0 ~?= Just 0
-      , f 65535 ~?= Just 65535
-      , f 65536 ~?= Nothing
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int Word32" ~:
-      let f = hush . Witch.tryFrom @Int @Word.Word32 in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Int in if toInteger x >= 4294967295
-        then f 4294967295 ~?= Just 4294967295
-        else f x ~?= Just (fromIntegral x)
-      , let x = maxBound :: Int in if toInteger x >= 4294967296
-        then f 4294967296 ~?= Nothing
-        else f x ~?= Just (fromIntegral x)
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int Word64" ~:
-      let f = hush . Witch.tryFrom @Int @Word.Word64 in
-      [ f 0 ~?= Just 0
-      , f maxBound ~?= Just (fromIntegral (maxBound :: Int))
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int Word" ~:
-      let f = hush . Witch.tryFrom @Int @Word in
-      [ f 0 ~?= Just 0
-      , f maxBound ~?= Just (fromIntegral (maxBound :: Int))
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int Natural" ~:
-      let f = hush . Witch.tryFrom @Int @Natural.Natural in
-      [ f 0 ~?= Just 0
-      , f maxBound ~?= Just (fromIntegral (maxBound :: Int))
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Int Float" ~:
-      let f = hush . Witch.tryFrom @Int @Float in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      , f (-16777215) ~?= Just (-16777215)
-      , f (-16777216) ~?= Nothing
-      ]
-    , "TryFrom Int Double" ~:
-      let f = hush . Witch.tryFrom @Int @Double in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Int in if toInteger x >= 9007199254740991
-        then f 9007199254740991 ~?= Just 9007199254740991
-        else f x ~?= Just (fromIntegral x)
-      , let x = maxBound :: Int in if toInteger x >= 9007199254740992
-        then f 9007199254740992 ~?= Nothing
-        else f x ~?= Just (fromIntegral x)
-      , let x = minBound :: Int in if toInteger x <= (-9007199254740991)
-        then f (-9007199254740991) ~?= Just (-9007199254740991)
-        else f x ~?= Just (fromIntegral x)
-      , let x = minBound :: Int in if toInteger x <= (-9007199254740992)
-        then f (-9007199254740992) ~?= Nothing
-        else f x ~?= Just (fromIntegral x)
-      ]
-
-    -- Integer
-
-    , "TryFrom Integer Int8" ~:
-      let f = hush . Witch.tryFrom @Integer @Int.Int8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f 128 ~?= Nothing
-      , f (-128) ~?= Just (-128)
-      , f (-129) ~?= Nothing
-      ]
-    , "TryFrom Integer Int16" ~:
-      let f = hush . Witch.tryFrom @Integer @Int.Int16 in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f 32768 ~?= Nothing
-      , f (-32768) ~?= Just (-32768)
-      , f (-32769) ~?= Nothing
-      ]
-    , "TryFrom Integer Int32" ~:
-      let f = hush . Witch.tryFrom @Integer @Int.Int32 in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , f 2147483648 ~?= Nothing
-      , f (-2147483648) ~?= Just (-2147483648)
-      , f (-2147483649) ~?= Nothing
-      ]
-    , "TryFrom Integer Int64" ~:
-      let f = hush . Witch.tryFrom @Integer @Int.Int64 in
-      [ f 0 ~?= Just 0
-      , f 9223372036854775807 ~?= Just 9223372036854775807
-      , f 9223372036854775808 ~?= Nothing
-      , f (-9223372036854775808) ~?= Just (-9223372036854775808)
-      , f (-9223372036854775809) ~?= Nothing
-      ]
-    , "TryFrom Integer Int" ~:
-      let f = hush . Witch.tryFrom @Integer @Int in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Int in f (fromIntegral x) ~?= Just x
-      , let x = toInteger (maxBound :: Int) + 1 in f x ~?= Nothing
-      , let x = minBound :: Int in f (fromIntegral x) ~?= Just x
-      , let x = toInteger (minBound :: Int) - 1 in f x ~?= Nothing
-      ]
-    , "TryFrom Integer Word8" ~:
-      let f = hush . Witch.tryFrom @Integer @Word.Word8 in
-      [ f 0 ~?= Just 0
-      , f 255 ~?= Just 255
-      , f 256 ~?= Nothing
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Integer Word16" ~:
-      let f = hush . Witch.tryFrom @Integer @Word.Word16 in
-      [ f 0 ~?= Just 0
-      , f 65535 ~?= Just 65535
-      , f 65536 ~?= Nothing
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Integer Word32" ~:
-      let f = hush . Witch.tryFrom @Integer @Word.Word32 in
-      [ f 0 ~?= Just 0
-      , f 4294967295 ~?= Just 4294967295
-      , f 4294967296 ~?= Nothing
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Integer Word64" ~:
-      let f = hush . Witch.tryFrom @Integer @Word.Word64 in
-      [ f 0 ~?= Just 0
-      , f 18446744073709551615 ~?= Just 18446744073709551615
-      , f 18446744073709551616 ~?= Nothing
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Integer Word" ~:
-      let f = hush . Witch.tryFrom @Integer @Word in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Word in f (fromIntegral x) ~?= Just x
-      , let x = toInteger (maxBound :: Word) + 1 in f x ~?= Nothing
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Integer Natural" ~:
-      let f = hush . Witch.tryFrom @Integer @Natural.Natural in
-      [ f 0 ~?= Just 0
-      , f 18446744073709551616 ~?= Just 18446744073709551616
-      , f (-1) ~?= Nothing
-      ]
-    , "TryFrom Integer Float" ~:
-      let f = hush . Witch.tryFrom @Integer @Float in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      , f (-16777215) ~?= Just (-16777215)
-      , f (-16777216) ~?= Nothing
-      ]
-    , "TryFrom Integer Double" ~:
-      let f = hush . Witch.tryFrom @Integer @Double in
-      [ f 0 ~?= Just 0
-      , f 9007199254740991 ~?= Just 9007199254740991
-      , f 9007199254740992 ~?= Nothing
-      , f (-9007199254740991) ~?= Just (-9007199254740991)
-      , f (-9007199254740992) ~?= Nothing
-      ]
-
-    -- Word8
-
-    , "From Word8 Word16" ~:
-      let f = Witch.from @Word.Word8 @Word.Word16 in
-      [ f 0 ~?= 0
-      , f 255 ~?= 255
-      ]
-    , "From Word8 Word32" ~:
-      let f = Witch.from @Word.Word8 @Word.Word32 in
-      [ f 0 ~?= 0
-      , f 255 ~?= 255
-      ]
-    , "From Word8 Word64" ~:
-      let f = Witch.from @Word.Word8 @Word.Word64 in
-      [ f 0 ~?= 0
-      , f 255 ~?= 255
-      ]
-    , "From Word8 Word" ~:
-      let f = Witch.from @Word.Word8 @Word in
-      [ f 0 ~?= 0
-      , f 255 ~?= 255
-      ]
-    , "From Word8 Natural" ~:
-      let f = Witch.from @Word.Word8 @Natural.Natural in
-      [ f 0 ~?= 0
-      , f 255 ~?= 255
-      ]
-    , "TryFrom Word8 Int8" ~:
-      let f = hush . Witch.tryFrom @Word.Word8 @Int.Int8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f 128 ~?= Nothing
-      ]
-    , "From Word8 Int16" ~:
-      let f = Witch.from @Word.Word8 @Int.Int16 in
-      [ f 0 ~?= 0
-      , f 255 ~?= 255
-      ]
-    , "From Word8 Int32" ~:
-      let f = Witch.from @Word.Word8 @Int.Int32 in
-      [ f 0 ~?= 0
-      , f 255 ~?= 255
-      ]
-    , "From Word8 Int64" ~:
-      let f = Witch.from @Word.Word8 @Int.Int64 in
-      [ f 0 ~?= 0
-      , f 255 ~?= 255
-      ]
-    , "From Word8 Int" ~:
-      let f = Witch.from @Word.Word8 @Int in
-      [ f 0 ~?= 0
-      , f 255 ~?= 255
-      ]
-    , "From Word8 Integer" ~:
-      let f = Witch.from @Word.Word8 @Integer in
-      [ f 0 ~?= 0
-      , f 255 ~?= 255
-      ]
-    , "From Word8 Float" ~:
-      let f = Witch.from @Word.Word8 @Float in
-      [ f 0 ~?= 0
-      , f 255 ~?= 255
-      ]
-    , "From Word8 Double" ~:
-      let f = Witch.from @Word.Word8 @Double in
-      [ f 0 ~?= 0
-      , f 255 ~?= 255
-      ]
-
-    -- Word16
-
-    , "TryFrom Word16 Word8" ~:
-      let f = hush . Witch.tryFrom @Word.Word16 @Word.Word8 in
-      [ f 0 ~?= Just 0
-      , f 255 ~?= Just 255
-      , f 256 ~?= Nothing
-      ]
-    , "From Word16 Word32" ~:
-      let f = Witch.from @Word.Word16 @Word.Word32 in
-      [ f 0 ~?= 0
-      , f 65535 ~?= 65535
-      ]
-    , "From Word16 Word64" ~:
-      let f = Witch.from @Word.Word16 @Word.Word64 in
-      [ f 0 ~?= 0
-      , f 65535 ~?= 65535
-      ]
-    , "From Word16 Word" ~:
-      let f = Witch.from @Word.Word16 @Word in
-      [ f 0 ~?= 0
-      , f 65535 ~?= 65535
-      ]
-    , "From Word16 Natural" ~:
-      let f = Witch.from @Word.Word16 @Natural.Natural in
-      [ f 0 ~?= 0
-      , f 65535 ~?= 65535
-      ]
-    , "TryFrom Word16 Int8" ~:
-      let f = hush . Witch.tryFrom @Word.Word16 @Int.Int8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f 128 ~?= Nothing
-      ]
-    , "TryFrom Word16 Int16" ~:
-      let f = hush . Witch.tryFrom @Word.Word16 @Int.Int16 in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f 32768 ~?= Nothing
-      ]
-    , "From Word16 Int32" ~:
-      let f = Witch.from @Word.Word16 @Int.Int32 in
-      [ f 0 ~?= 0
-      , f 65535 ~?= 65535
-      ]
-    , "From Word16 Int64" ~:
-      let f = Witch.from @Word.Word16 @Int.Int64 in
-      [ f 0 ~?= 0
-      , f 65535 ~?= 65535
-      ]
-    , "From Word16 Int" ~:
-      let f = Witch.from @Word.Word16 @Int in
-      [ f 0 ~?= 0
-      , f 65535 ~?= 65535
-      ]
-    , "From Word16 Integer" ~:
-      let f = Witch.from @Word.Word16 @Integer in
-      [ f 0 ~?= 0
-      , f 65535 ~?= 65535
-      ]
-    , "From Word16 Float" ~:
-      let f = Witch.from @Word.Word16 @Float in
-      [ f 0 ~?= 0
-      , f 65535 ~?= 65535
-      ]
-    , "From Word16 Double" ~:
-      let f = Witch.from @Word.Word16 @Double in
-      [ f 0 ~?= 0
-      , f 65535 ~?= 65535
-      ]
-
-    -- Word32
-
-    , "TryFrom Word32 Word8" ~:
-      let f = hush . Witch.tryFrom @Word.Word32 @Word.Word8 in
-      [ f 0 ~?= Just 0
-      , f 255 ~?= Just 255
-      , f 256 ~?= Nothing
-      ]
-    , "TryFrom Word32 Word16" ~:
-      let f = hush . Witch.tryFrom @Word.Word32 @Word.Word16 in
-      [ f 0 ~?= Just 0
-      , f 65535 ~?= Just 65535
-      , f 65536 ~?= Nothing
-      ]
-    , "From Word32 Word64" ~:
-      let f = Witch.from @Word.Word32 @Word.Word64 in
-      [ f 0 ~?= 0
-      , f 4294967295 ~?= 4294967295
-      ]
-    , "TryFrom Word32 Word" ~:
-      let f = hush . Witch.tryFrom @Word.Word32 @Word in
-      [ f 0 ~?= Just 0
-      , f 4294967295 ~?= Just 4294967295
-      ]
-    , "From Word32 Natural" ~:
-      let f = Witch.from @Word.Word32 @Natural.Natural in
-      [ f 0 ~?= 0
-      , f 4294967295 ~?= 4294967295
-      ]
-    , "TryFrom Word32 Int8" ~:
-      let f = hush . Witch.tryFrom @Word.Word32 @Int.Int8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f 128 ~?= Nothing
-      ]
-    , "TryFrom Word32 Int16" ~:
-      let f = hush . Witch.tryFrom @Word.Word32 @Int.Int16 in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f 32768 ~?= Nothing
-      ]
-    , "TryFrom Word32 Int32" ~:
-      let f = hush . Witch.tryFrom @Word.Word32 @Int.Int32 in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , f 2147483648 ~?= Nothing
-      ]
-    , "From Word32 Int64" ~:
-      let f = Witch.from @Word.Word32 @Int.Int64 in
-      [ f 0 ~?= 0
-      , f 4294967295 ~?= 4294967295
-      ]
-    , "TryFrom Word32 Int" ~:
-      let f = hush . Witch.tryFrom @Word.Word32 @Int in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Int in if toInteger x >= 4294967295
-        then f 4294967295 ~?= Just 4294967295
-        else f (fromIntegral x) ~?= Just x
-      ]
-    , "From Word32 Integer" ~:
-      let f = Witch.from @Word.Word32 @Integer in
-      [ f 0 ~?= 0
-      , f 4294967295 ~?= 4294967295
-      ]
-    , "TryFrom Word32 Float" ~:
-      let f = hush . Witch.tryFrom @Word.Word32 @Float in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      ]
-    , "From Word32 Double" ~:
-      let f = Witch.from @Word.Word32 @Double in
-      [ f 0 ~?= 0
-      , f 4294967295 ~?= 4294967295
-      ]
-
-    -- Word64
-
-    , "TryFrom Word64 Word8" ~:
-      let f = hush . Witch.tryFrom @Word.Word64 @Word.Word8 in
-      [ f 0 ~?= Just 0
-      , f 255 ~?= Just 255
-      , f 256 ~?= Nothing
-      ]
-    , "TryFrom Word64 Word16" ~:
-      let f = hush . Witch.tryFrom @Word.Word64 @Word.Word16 in
-      [ f 0 ~?= Just 0
-      , f 65535 ~?= Just 65535
-      , f 65536 ~?= Nothing
-      ]
-    , "TryFrom Word64 Word32" ~:
-      let f = hush . Witch.tryFrom @Word.Word64 @Word.Word32 in
-      [ f 0 ~?= Just 0
-      , f 4294967295 ~?= Just 4294967295
-      , f 4294967296 ~?= Nothing
-      ]
-    , "TryFrom Word64 Word" ~:
-      let f = hush . Witch.tryFrom @Word.Word64 @Word in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Word in if toInteger x >= 18446744073709551615
-        then f 18446744073709551615 ~?= Just 18446744073709551615
-        else f (fromIntegral x) ~?= Just x
-      ]
-    , "From Word64 Natural" ~:
-      let f = Witch.from @Word.Word64 @Natural.Natural in
-      [ f 0 ~?= 0
-      , f 18446744073709551615 ~?= 18446744073709551615
-      ]
-    , "TryFrom Word64 Int8" ~:
-      let f = hush . Witch.tryFrom @Word.Word64 @Int.Int8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f 128 ~?= Nothing
-      ]
-    , "TryFrom Word64 Int16" ~:
-      let f = hush . Witch.tryFrom @Word.Word64 @Int.Int16 in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f 32768 ~?= Nothing
-      ]
-    , "TryFrom Word64 Int32" ~:
-      let f = hush . Witch.tryFrom @Word.Word64 @Int.Int32 in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , f 2147483648 ~?= Nothing
-      ]
-    , "TryFrom Word64 Int64" ~:
-      let f = hush . Witch.tryFrom @Word.Word64 @Int.Int64 in
-      [ f 0 ~?= Just 0
-      , f 9223372036854775807 ~?= Just 9223372036854775807
-      , f 9223372036854775808 ~?= Nothing
-      ]
-    , "TryFrom Word64 Int" ~:
-      let f = hush . Witch.tryFrom @Word.Word64 @Int in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Int in hush (Witch.tryFrom @Word.Word64 @Int (fromIntegral x)) ~?= Just x
-      , let x = fromIntegral (maxBound :: Int) + 1 :: Word.Word64 in hush (Witch.tryFrom @Word.Word64 @Int x) ~?= Nothing
-      ]
-    , "From Word64 Integer" ~:
-      let f = Witch.from @Word.Word64 @Integer in
-      [ f 0 ~?= 0
-      , f 18446744073709551615 ~?= 18446744073709551615
-      ]
-    , "TryFrom Word64 Float" ~:
-      let f = hush . Witch.tryFrom @Word.Word64 @Float in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      ]
-    , "TryFrom Word64 Double" ~:
-      let f = hush . Witch.tryFrom @Word.Word64 @Double in
-      [ f 0 ~?= Just 0
-      , f 9007199254740991 ~?= Just 9007199254740991
-      , f 9007199254740992 ~?= Nothing
-      ]
-
-    -- Word
-
-    , "TryFrom Word Word8" ~:
-      let f = hush . Witch.tryFrom @Word @Word.Word8 in
-      [ f 0 ~?= Just 0
-      , f 255 ~?= Just 255
-      , f 256 ~?= Nothing
-      ]
-    , "TryFrom Word Word16" ~:
-      let f = hush . Witch.tryFrom @Word @Word.Word16 in
-      [ f 0 ~?= Just 0
-      , f 65535 ~?= Just 65535
-      , f 65536 ~?= Nothing
-      ]
-    , "TryFrom Word Word32" ~:
-      let f = hush . Witch.tryFrom @Word @Word.Word32 in
-      [ f 0 ~?= Just 0
-      , f 4294967295 ~?= Just 4294967295
-      , let x = maxBound :: Word in if toInteger x >= 4294967296
-        then f 4294967296 ~?= Nothing
-        else f x ~?= Just (fromIntegral x)
-      ]
-    , "From Word Word64" ~:
-      let f = Witch.from @Word @Word.Word64 in
-      [ f 0 ~?= 0
-      , f maxBound ~?= fromIntegral (maxBound :: Word)
-      ]
-    , "From Word Natural" ~:
-      let f = Witch.from @Word @Natural.Natural in
-      [ f 0 ~?= 0
-      , f maxBound ~?= fromIntegral (maxBound :: Word)
-      ]
-    , "TryFrom Word Int8" ~:
-      let f = hush . Witch.tryFrom @Word @Int.Int8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f 128 ~?= Nothing
-      ]
-    , "TryFrom Word Int16" ~:
-      let f = hush . Witch.tryFrom @Word @Int.Int16 in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f 32768 ~?= Nothing
-      ]
-    , "TryFrom Word Int32" ~:
-      let f = hush . Witch.tryFrom @Word @Int.Int32 in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , f 2147483648 ~?= Nothing
-      ]
-    , "TryFrom Word Int64" ~:
-      let f = hush . Witch.tryFrom @Word @Int.Int64 in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Word in if toInteger x >= 9223372036854775807
-        then f 9223372036854775807 ~?= Just 9223372036854775807
-        else f x ~?= Just (fromIntegral x)
-      , let x = maxBound :: Word in if toInteger x >= 9223372036854775808
-        then f 9223372036854775808 ~?= Nothing
-        else f x ~?= Just (fromIntegral x)
-      ]
-    , "TryFrom Word Int" ~:
-      let f = hush . Witch.tryFrom @Word @Int in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Int in hush (Witch.tryFrom @Word @Int (fromIntegral x)) ~?= Just x
-      , let x = fromIntegral (maxBound :: Int) + 1 :: Word in hush (Witch.tryFrom @Word @Int x) ~?= Nothing
-      ]
-    , "From Word Integer" ~:
-      let f = Witch.from @Word @Integer in
-      [ f 0 ~?= 0
-      , f maxBound ~?= fromIntegral (maxBound :: Word)
-      ]
-    , "TryFrom Word Float" ~:
-      let f = hush . Witch.tryFrom @Word @Float in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      ]
-    , "TryFrom Word Double" ~:
-      let f = hush . Witch.tryFrom @Word @Double in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Word in if toInteger x >= 9007199254740991
-        then f 9007199254740991 ~?= Just 9007199254740991
-        else f x ~?= Just (fromIntegral x)
-      , let x = maxBound :: Word in if toInteger x >= 9007199254740992
-        then f 9007199254740992 ~?= Nothing
-        else f x ~?= Just (fromIntegral x)
-      ]
-
-    -- Natural
-
-    , "TryFrom Natural Word8" ~:
-      let f = hush . Witch.tryFrom @Natural.Natural @Word.Word8 in
-      [ f 0 ~?= Just 0
-      , f 255 ~?= Just 255
-      , f 256 ~?= Nothing
-      ]
-    , "TryFrom Natural Word16" ~:
-      let f = hush . Witch.tryFrom @Natural.Natural @Word.Word16 in
-      [ f 0 ~?= Just 0
-      , f 65535 ~?= Just 65535
-      , f 65536 ~?= Nothing
-      ]
-    , "TryFrom Natural Word32" ~:
-      let f = hush . Witch.tryFrom @Natural.Natural @Word.Word32 in
-      [ f 0 ~?= Just 0
-      , f 4294967295 ~?= Just 4294967295
-      , f 4294967296 ~?= Nothing
-      ]
-    , "TryFrom Natural Word64" ~:
-      let f = hush . Witch.tryFrom @Natural.Natural @Word.Word64 in
-      [ f 0 ~?= Just 0
-      , f 18446744073709551615 ~?= Just 18446744073709551615
-      , f 18446744073709551616 ~?= Nothing
-      ]
-    , "TryFrom Natural Word" ~:
-      let f = hush . Witch.tryFrom @Natural.Natural @Word in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Word in hush (Witch.tryFrom @Natural.Natural @Word (fromIntegral x)) ~?= Just x
-      , let x = fromIntegral (maxBound :: Word) + 1 :: Natural.Natural in hush (Witch.tryFrom @Natural.Natural @Word x) ~?= Nothing
-      ]
-    , "TryFrom Natural Int8" ~:
-      let f = hush . Witch.tryFrom @Natural.Natural @Int.Int8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f 128 ~?= Nothing
-      ]
-    , "TryFrom Natural Int16" ~:
-      let f = hush . Witch.tryFrom @Natural.Natural @Int.Int16 in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f 32768 ~?= Nothing
-      ]
-    , "TryFrom Natural Int32" ~:
-      let f = hush . Witch.tryFrom @Natural.Natural @Int.Int32 in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , f 2147483648 ~?= Nothing
-      ]
-    , "TryFrom Natural Int64" ~:
-      let f = hush . Witch.tryFrom @Natural.Natural @Int.Int64 in
-      [ f 0 ~?= Just 0
-      , f 9223372036854775807 ~?= Just 9223372036854775807
-      , f 9223372036854775808 ~?= Nothing
-      ]
-    , "TryFrom Natural Int" ~:
-      let f = hush . Witch.tryFrom @Natural.Natural @Int in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Int in hush (Witch.tryFrom @Natural.Natural @Int (fromIntegral x)) ~?= Just x
-      , let x = fromIntegral (maxBound :: Int) + 1 :: Natural.Natural in hush (Witch.tryFrom @Natural.Natural @Int x) ~?= Nothing
-      ]
-    , "From Natural Integer" ~:
-      let f = Witch.from @Natural.Natural @Integer in
-      [ f 0 ~?= 0
-      , f 9223372036854775808 ~?= 9223372036854775808
-      ]
-    , "TryFrom Natural Float" ~:
-      let f = hush . Witch.tryFrom @Natural.Natural @Float in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      ]
-    , "TryFrom Natural Double" ~:
-      let f = hush . Witch.tryFrom @Natural.Natural @Double in
-      [ f 0 ~?= Just 0
-      , f 9007199254740991 ~?= Just 9007199254740991
-      , f 9007199254740992 ~?= Nothing
-      ]
-
-    -- Float
-
-    , "TryFrom Float Int8" ~:
-      let f = hush . Witch.tryFrom @Float @Int.Int8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f 128 ~?= Nothing
-      , f (-128) ~?= Just (-128)
-      , f (-129) ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Float Int16" ~:
-      let f = hush . Witch.tryFrom @Float @Int.Int16 in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f 32768 ~?= Nothing
-      , f (-32768) ~?= Just (-32768)
-      , f (-32769) ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Float Int32" ~:
-      let f = hush . Witch.tryFrom @Float @Int.Int32 in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      , f (-16777215) ~?= Just (-16777215)
-      , f (-16777216) ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Float Int64" ~:
-      let f = hush . Witch.tryFrom @Float @Int.Int64 in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      , f (-16777215) ~?= Just (-16777215)
-      , f (-16777216) ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Float Int" ~:
-      let f = hush . Witch.tryFrom @Float @Int in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      , f (-16777215) ~?= Just (-16777215)
-      , f (-16777216) ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Float Integer" ~:
-      let f = hush . Witch.tryFrom @Float @Integer in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      , f (-16777215) ~?= Just (-16777215)
-      , f (-16777216) ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Float Word8" ~:
-      let f = hush . Witch.tryFrom @Float @Word.Word8 in
-      [ f 0 ~?= Just 0
-      , f 255 ~?= Just 255
-      , f 256 ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Float Word16" ~:
-      let f = hush . Witch.tryFrom @Float @Word.Word16 in
-      [ f 0 ~?= Just 0
-      , f 65535 ~?= Just 65535
-      , f 65536 ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Float Word32" ~:
-      let f = hush . Witch.tryFrom @Float @Word.Word32 in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Float Word64" ~:
-      let f = hush . Witch.tryFrom @Float @Word.Word64 in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Float Word" ~:
-      let f = hush . Witch.tryFrom @Float @Word in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Float Natural" ~:
-      let f = hush . Witch.tryFrom @Float @Natural.Natural in
-      [ f 0 ~?= Just 0
-      , f 16777215 ~?= Just 16777215
-      , f 16777216 ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Float Rational" ~:
-      let f = hush . Witch.tryFrom @Float @Rational in
-      [ f 0 ~?= Just 0
-      , f (-0) ~?= Just 0
-      , f 0.5 ~?= Just 0.5
-      , f (-0.5) ~?= Just (-0.5)
-      , f 16777215 ~?= Just 16777215
-      , f (-16777215) ~?= Just (-16777215)
-      , f 16777216 ~?= Just 16777216
-      , f (-16777216) ~?= Just (-16777216)
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "From Float Double" ~:
-      let f = Witch.from @Float @Double in
-      [ f 0 ~?= 0
-      , f 0.5 ~?= 0.5
-      , f (-0.5) ~?= (-0.5)
-      , TestCase $ let x = f (0 / 0) in assertBool (show x) $ isNaN x
-      , f (1 / 0) ~?= (1 / 0)
-      , f (-1 / 0) ~?= (-1 / 0)
-      ]
-
-    -- Double
-
-    , "TryFrom Double Int8" ~:
-      let f = hush . Witch.tryFrom @Double @Int.Int8 in
-      [ f 0 ~?= Just 0
-      , f 127 ~?= Just 127
-      , f 128 ~?= Nothing
-      , f (-128) ~?= Just (-128)
-      , f (-129) ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Double Int16" ~:
-      let f = hush . Witch.tryFrom @Double @Int.Int16 in
-      [ f 0 ~?= Just 0
-      , f 32767 ~?= Just 32767
-      , f 32768 ~?= Nothing
-      , f (-32768) ~?= Just (-32768)
-      , f (-32769) ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Double Int32" ~:
-      let f = hush . Witch.tryFrom @Double @Int.Int32 in
-      [ f 0 ~?= Just 0
-      , f 2147483647 ~?= Just 2147483647
-      , f 2147483648 ~?= Nothing
-      , f (-2147483648) ~?= Just (-2147483648)
-      , f (-2147483649) ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Double Int64" ~:
-      let f = hush . Witch.tryFrom @Double @Int.Int64 in
-      [ f 0 ~?= Just 0
-      , f 9007199254740991 ~?= Just 9007199254740991
-      , f 9007199254740992 ~?= Nothing
-      , f (-9007199254740991) ~?= Just (-9007199254740991)
-      , f (-9007199254740992) ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Double Int" ~:
-      let f = hush . Witch.tryFrom @Double @Int in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Int in if toInteger x >= 9007199254740991
-        then f 9007199254740991 ~?= Just 9007199254740991
-        else f (fromIntegral x) ~?= Just x
-      , f 9007199254740992 ~?= Nothing
-      , let x = minBound :: Int in if toInteger x <= (-9007199254740991)
-        then f (-9007199254740991) ~?= Just (-9007199254740991)
-        else f (fromIntegral x) ~?= Just x
-      , f (-9007199254740992) ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Double Integer" ~:
-      let f = hush . Witch.tryFrom @Double @Integer in
-      [ f 0 ~?= Just 0
-      , f 9007199254740991 ~?= Just 9007199254740991
-      , f 9007199254740992 ~?= Nothing
-      , f (-9007199254740991) ~?= Just (-9007199254740991)
-      , f (-9007199254740992) ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Double Word8" ~:
-      let f = hush . Witch.tryFrom @Double @Word.Word8 in
-      [ f 0 ~?= Just 0
-      , f 255 ~?= Just 255
-      , f 256 ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Double Word16" ~:
-      let f = hush . Witch.tryFrom @Double @Word.Word16 in
-      [ f 0 ~?= Just 0
-      , f 65535 ~?= Just 65535
-      , f 65536 ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Double Word32" ~:
-      let f = hush . Witch.tryFrom @Double @Word.Word32 in
-      [ f 0 ~?= Just 0
-      , f 4294967295 ~?= Just 4294967295
-      , f 4294967296 ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Double Word64" ~:
-      let f = hush . Witch.tryFrom @Double @Word.Word64 in
-      [ f 0 ~?= Just 0
-      , f 9007199254740991 ~?= Just 9007199254740991
-      , f 9007199254740992 ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Double Word" ~:
-      let f = hush . Witch.tryFrom @Double @Word in
-      [ f 0 ~?= Just 0
-      , let x = maxBound :: Word in if toInteger x >= 9007199254740991
-        then f 9007199254740991 ~?= Just 9007199254740991
-        else f (fromIntegral x) ~?= Just x
-      , f 9007199254740992 ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Double Natural" ~:
-      let f = hush . Witch.tryFrom @Double @Natural.Natural in
-      [ f 0 ~?= Just 0
-      , f 9007199254740991 ~?= Just 9007199254740991
-      , f 9007199254740992 ~?= Nothing
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "TryFrom Double Rational" ~:
-      let f = hush . Witch.tryFrom @Double @Rational in
-      [ f 0 ~?= Just 0
-      , f (-0) ~?= Just 0
-      , f 0.5 ~?= Just 0.5
-      , f (-0.5) ~?= Just (-0.5)
-      , f 9007199254740991 ~?= Just 9007199254740991
-      , f (-9007199254740991) ~?= Just (-9007199254740991)
-      , f 9007199254740992 ~?= Just 9007199254740992
-      , f (-9007199254740992) ~?= Just (-9007199254740992)
-      , f (0 / 0) ~?= Nothing
-      , f (1 / 0) ~?= Nothing
-      , f (-1 / 0) ~?= Nothing
-      ]
-    , "From Double Float" ~:
-      let f = Witch.from @Double @Float in
-      [ f 0 ~?= 0
-      , f 0.5 ~?= 0.5
-      , f (-0.5) ~?= (-0.5)
-      , TestCase $ let x = f (0 / 0) in assertBool (show x) $ isNaN x
-      , f (1 / 0) ~?= (1 / 0)
-      , f (-1 / 0) ~?= (-1 / 0)
-      ]
-
-    -- Ratio
-
-    , "From a (Ratio a)" ~:
-      let f = Witch.from @Int @(Ratio.Ratio Int) in
-      [ Witch.from @Integer @Rational 0 ~?= 0
-      , f 0 ~?= 0
-      ]
-    , "TryFrom (Ratio a) a" ~:
-      let f = hush . Witch.tryFrom @(Ratio.Ratio Int) @Int in
-      [ hush (Witch.tryFrom @Rational @Integer 0) ~?= Just 0
-      , hush (Witch.tryFrom @Rational @Integer 0.5) ~?= Nothing
-      , f 0 ~?= Just 0
-      , f 0.5 ~?= Nothing
-      ]
-    , "From Rational Float" ~:
-      let f = Witch.from @Rational @Float in
-      [ f 0 ~?= 0
-      , f 0.5 ~?= 0.5
-      , f (-0.5) ~?= (-0.5)
-      ]
-    , "From Rational Double" ~:
-      let f = Witch.from @Rational @Double in
-      [ f 0 ~?= 0
-      , f 0.5 ~?= 0.5
-      , f (-0.5) ~?= (-0.5)
-      ]
-    , "TryFrom Rational (Fixed a)" ~:
-      let f = hush . Witch.tryFrom @Rational @Fixed.Deci in
-      [ hush (Witch.tryFrom @Rational @Fixed.Uni 1) ~?= Just 1
-      , hush (Witch.tryFrom @Rational @Fixed.Uni 1.2) ~?= Nothing
-      , f 0.1 ~?= Just 0.1
-      , f 1.2 ~?= Just 1.2
-      , f 12.3 ~?= Just 12.3
-      , f 0.12 ~?= Nothing
-      ]
-
-    -- Fixed
-
-    , "From Integer (Fixed a)" ~:
-      let f = Witch.from @Integer @Fixed.Deci in
-      [ Witch.from @Integer @Fixed.Uni 1 ~?= 1
-      , f 1 ~?= 0.1
-      , f 10 ~?= 1
-      , f 120 ~?= 12
-      ]
-    , "From (Fixed a) Integer" ~:
-      let f = Witch.from @Fixed.Deci @Integer in
-      [ Witch.from @Fixed.Uni @Integer 1 ~?= 1
-      , f 0.1 ~?= 1
-      , f 1 ~?= 10
-      , f 12 ~?= 120
-      ]
-    , "From (Fixed a) Rational" ~:
-      let f = Witch.from @Fixed.Deci @Rational in
-      [ Witch.from @Fixed.Uni @Rational 1 ~?= 1
-      , f 0.1 ~?= 0.1
-      , f 1 ~?= 1
-      , f 12 ~?= 12
-      ]
-
-    -- Complex
-
-    , "From a (Complex a)" ~:
-      let f = Witch.from @Float @(Complex.Complex Float) in
-      [ Witch.from @Double @(Complex.Complex Double) 1 ~?= 1
-      , f 1 ~?= 1
-      ]
-    , "TryFrom (Complex a) a" ~:
-      let f = hush . Witch.tryFrom @(Complex.Complex Float) @Float in
-      [ hush (Witch.tryFrom @(Complex.Complex Double) @Double 1) ~?= Just 1
-      , hush (Witch.tryFrom @(Complex.Complex Double) @Double (0 Complex.:+ 1)) ~?= Nothing
-      , f 1 ~?= Just 1
-      , f (0 Complex.:+ 1) ~?= Nothing
-      ]
-
-    -- NonEmpty
-
-    , "TryFrom [a] (NonEmpty a)" ~:
-      let f = hush . Witch.tryFrom @[Int] @(NonEmpty.NonEmpty Int) in
-      [ f [] ~?= Nothing
-      , f [1] ~?= Just (1 NonEmpty.:| [])
-      , f [1, 2] ~?= Just (1 NonEmpty.:| [2])
-      ]
-    , "From (NonEmpty a) [a]" ~:
-      let f = Witch.from @(NonEmpty.NonEmpty Int) @[Int] in
-      [ f (1 NonEmpty.:| []) ~?= [1]
-      , f (1 NonEmpty.:| [2]) ~?= [1, 2]
-      ]
-
-    -- Set
-
-    , "From [a] (Set a)" ~:
-      let f = Witch.from @[Char] @(Set.Set Char) in
-      [ f [] ~?= Set.fromList []
-      , f ['a'] ~?= Set.fromList ['a']
-      , f ['a', 'b'] ~?= Set.fromList ['a', 'b']
-      , f ['a', 'a'] ~?= Set.fromList ['a']
-      ]
-    , "From (Set a) [a]" ~:
-      let f = Witch.from @(Set.Set Char) @[Char] in
-      [ f (Set.fromList []) ~?= []
-      , f (Set.fromList ['a']) ~?= ['a']
-      , f (Set.fromList ['a', 'b']) ~?= ['a', 'b']
-      ]
-
-    -- IntSet
-
-    , "From [Int] IntSet" ~:
-      let f = Witch.from @[Int] @IntSet.IntSet in
-      [ f [] ~?= IntSet.fromList []
-      , f [1] ~?= IntSet.fromList [1]
-      , f [1, 2] ~?= IntSet.fromList [1, 2]
-      ]
-    , "From IntSet [Int]" ~:
-      let f = Witch.from @IntSet.IntSet @[Int] in
-      [ f (IntSet.fromList []) ~?= []
-      , f (IntSet.fromList [1]) ~?= [1]
-      , f (IntSet.fromList [1, 2]) ~?= [1, 2]
-      ]
-
-    -- Map
-
-    , "From [(k, v)] (Map k v)" ~:
-      let f = Witch.from @[(Char, Int)] @(Map.Map Char Int) in
-      [ f [] ~?= Map.empty
-      , f [('a', 1)] ~?= Map.fromList [('a', 1)]
-      , f [('a', 1), ('b', 2)] ~?= Map.fromList [('a', 1), ('b', 2)]
-      , f [('a', 1), ('a', 2)] ~?= Map.fromList [('a', 2)]
-      ]
-    , "From (Map k v) [(k, v)]" ~:
-      let f = Witch.from @(Map.Map Char Int) @[(Char, Int)] in
-      [ f Map.empty ~?= []
-      , f (Map.fromList [('a', 1)]) ~?= [('a', 1)]
-      , f (Map.fromList [('a', 1), ('b', 2)]) ~?= [('a', 1), ('b', 2)]
-      ]
-
-    -- IntMap
-
-    , "From [(Int, v)] (IntMap v)" ~:
-      let f = Witch.from @[(Int, Char)] @(IntMap.IntMap Char) in
-      [ f [] ~?= IntMap.fromList []
-      , f [(1, 'a')] ~?= IntMap.fromList [(1, 'a')]
-      , f [(1, 'a'), (2, 'b')] ~?= IntMap.fromList [(1, 'a'), (2, 'b')]
-      , f [(1, 'a'), (1, 'b')] ~?= IntMap.fromList [(1, 'b')]
-      ]
-    , "From (IntMap v) [(Int, v)]" ~:
-      let f = Witch.from @(IntMap.IntMap Char) @[(Int, Char)] in
-      [ f (IntMap.fromList []) ~?= []
-      , f (IntMap.fromList [(1, 'a')]) ~?= [(1, 'a')]
-      , f (IntMap.fromList [(1, 'a'), (2, 'b')]) ~?= [(1, 'a'), (2, 'b')]
-      ]
-
-    -- Seq
-
-    , "From [a] (Seq a)" ~:
-      let f = Witch.from @[Int] @(Seq.Seq Int) in
-      [ f [] ~?= Seq.fromList []
-      , f [1] ~?= Seq.fromList [1]
-      , f [1, 2] ~?= Seq.fromList [1, 2]
-      ]
-    , "From (Seq a) [a]" ~:
-      let f = Witch.from @(Seq.Seq Int) @[Int] in
-      [ f (Seq.fromList []) ~?= []
-      , f (Seq.fromList [1]) ~?= [1]
-      , f (Seq.fromList [1, 2]) ~?= [1, 2]
-      ]
-
-    -- ByteString
-
-    , "From [Word8] ByteString" ~:
-      let f = Witch.from @[Word.Word8] @ByteString.ByteString in
-      [ f [] ~?= ByteString.pack []
-      , f [0x00] ~?= ByteString.pack [0x00]
-      , f [0x0f, 0xf0] ~?= ByteString.pack [0x0f, 0xf0]
-      ]
-    , "From ByteString [Word8]" ~:
-      let f = Witch.from @ByteString.ByteString @[Word.Word8] in
-      [ f (ByteString.pack []) ~?= []
-      , f (ByteString.pack [0x00]) ~?= [0x00]
-      , f (ByteString.pack [0x0f, 0xf0]) ~?= [0x0f, 0xf0]
-      ]
-    , "From ByteString LazyByteString" ~:
-      let f = Witch.from @ByteString.ByteString @LazyByteString.ByteString in
-      [ f (ByteString.pack []) ~?= LazyByteString.pack []
-      , f (ByteString.pack [0x00]) ~?= LazyByteString.pack [0x00]
-      , f (ByteString.pack [0x0f, 0xf0]) ~?= LazyByteString.pack [0x0f, 0xf0]
-      ]
-    , "From ByteString ShortByteString" ~:
-      let f = Witch.from @ByteString.ByteString @ShortByteString.ShortByteString in
-      [ f (ByteString.pack []) ~?= ShortByteString.pack []
-      , f (ByteString.pack [0x00]) ~?= ShortByteString.pack [0x00]
-      , f (ByteString.pack [0x0f, 0xf0]) ~?= ShortByteString.pack [0x0f, 0xf0]
-      ]
-    , "TryFrom ByteString Text" ~:
-      let f = hush . Witch.tryFrom @ByteString.ByteString @Text.Text in
-      [ f (ByteString.pack []) ~?= Just (Text.pack "")
-      , f (ByteString.pack [0x61]) ~?= Just (Text.pack "a")
-      , f (ByteString.pack [0xff]) ~?= Nothing
-      ]
-    , "TryFrom ByteString LazyText" ~:
-      let f = hush . Witch.tryFrom @ByteString.ByteString @LazyText.Text in
-      [ f (ByteString.pack []) ~?= Just (LazyText.pack "")
-      , f (ByteString.pack [0x61]) ~?= Just (LazyText.pack "a")
-      , f (ByteString.pack [0xff]) ~?= Nothing
-      ]
-    , "TryFrom ByteString String" ~:
-      let f = hush . Witch.tryFrom @ByteString.ByteString @String in
-      [ f (ByteString.pack []) ~?= Just ""
-      , f (ByteString.pack [0x61]) ~?= Just "a"
-      , f (ByteString.pack [0xff]) ~?= Nothing
-      ]
-
-    -- LazyByteString
-
-    , "From [Word8] LazyByteString" ~:
-      let f = Witch.from @[Word.Word8] @LazyByteString.ByteString in
-      [ f [] ~?= LazyByteString.pack []
-      , f [0x00] ~?= LazyByteString.pack [0x00]
-      , f [0x0f, 0xf0] ~?= LazyByteString.pack [0x0f, 0xf0]
-      ]
-    , "From LazyByteString [Word8]" ~:
-      let f = Witch.from @LazyByteString.ByteString @[Word.Word8] in
-      [ f (LazyByteString.pack []) ~?= []
-      , f (LazyByteString.pack [0x00]) ~?= [0x00]
-      , f (LazyByteString.pack [0x0f, 0xf0]) ~?= [0x0f, 0xf0]
-      ]
-    , "From LazyByteString ByteString" ~:
-      let f = Witch.from @LazyByteString.ByteString @ByteString.ByteString in
-      [ f (LazyByteString.pack []) ~?= ByteString.pack []
-      , f (LazyByteString.pack [0x00]) ~?= ByteString.pack [0x00]
-      , f (LazyByteString.pack [0x0f, 0xf0]) ~?= ByteString.pack [0x0f, 0xf0]
-      ]
-    , "TryFrom LazyByteString LazyText" ~:
-      let f = hush . Witch.tryFrom @LazyByteString.ByteString @LazyText.Text in
-      [ f (LazyByteString.pack []) ~?= Just (LazyText.pack "")
-      , f (LazyByteString.pack [0x61]) ~?= Just (LazyText.pack "a")
-      , f (LazyByteString.pack [0xff]) ~?= Nothing
-      ]
-    , "TryFrom LazyByteString Text" ~:
-      let f = hush . Witch.tryFrom @LazyByteString.ByteString @Text.Text in
-      [ f (LazyByteString.pack []) ~?= Just (Text.pack "")
-      , f (LazyByteString.pack [0x61]) ~?= Just (Text.pack "a")
-      , f (LazyByteString.pack [0xff]) ~?= Nothing
-      ]
-    , "TryFrom LazyByteString String" ~:
-      let f = hush . Witch.tryFrom @LazyByteString.ByteString @String in
-      [ f (LazyByteString.pack []) ~?= Just ""
-      , f (LazyByteString.pack [0x61]) ~?= Just "a"
-      , f (LazyByteString.pack [0xff]) ~?= Nothing
-      ]
-
-    -- ShortByteString
-
-    , "From [Word8] ShortByteString" ~:
-      let f = Witch.from @[Word.Word8] @ShortByteString.ShortByteString in
-      [ f [] ~?= ShortByteString.pack []
-      , f [0x00] ~?= ShortByteString.pack [0x00]
-      , f [0x0f, 0xf0] ~?= ShortByteString.pack [0x0f, 0xf0]
-      ]
-    , "From ShortByteString [Word8]" ~:
-      let f = Witch.from @ShortByteString.ShortByteString @[Word.Word8] in
-      [ f (ShortByteString.pack []) ~?= []
-      , f (ShortByteString.pack [0x00]) ~?= [0x00]
-      , f (ShortByteString.pack [0x0f, 0xf0]) ~?= [0x0f, 0xf0]
-      ]
-    , "From ShortByteString ByteString" ~:
-      let f = Witch.from @ShortByteString.ShortByteString @ByteString.ByteString in
-      [ f (ShortByteString.pack []) ~?= ByteString.pack []
-      , f (ShortByteString.pack [0x00]) ~?= ByteString.pack [0x00]
-      , f (ShortByteString.pack [0x0f, 0xf0]) ~?= ByteString.pack [0x0f, 0xf0]
-      ]
-
-    -- Text
-
-    , "From Text LazyText" ~:
-      let f = Witch.from @Text.Text @LazyText.Text in
-      [ f (Text.pack "") ~?= LazyText.pack ""
-      , f (Text.pack "a") ~?= LazyText.pack "a"
-      , f (Text.pack "ab") ~?= LazyText.pack "ab"
-      ]
-    , "From Text ByteString" ~:
-      let f = Witch.from @Text.Text @ByteString.ByteString in
-      [ f (Text.pack "") ~?= ByteString.pack []
-      , f (Text.pack "a") ~?= ByteString.pack [0x61]
-      ]
-    , "From Text LazyByteString" ~:
-      let f = Witch.from @Text.Text @LazyByteString.ByteString in
-      [ f (Text.pack "") ~?= LazyByteString.pack []
-      , f (Text.pack "a") ~?= LazyByteString.pack [0x61]
-      ]
-
-    -- LazyText
-
-    , "From LazyText Text" ~:
-      let f = Witch.from @LazyText.Text @Text.Text in
-      [ f (LazyText.pack "") ~?= Text.pack ""
-      , f (LazyText.pack "a") ~?= Text.pack "a"
-      , f (LazyText.pack "ab") ~?= Text.pack "ab"
-      ]
-    , "From LazyText LazyByteString" ~:
-      let f = Witch.from @LazyText.Text @LazyByteString.ByteString in
-      [ f (LazyText.pack "") ~?= LazyByteString.pack []
-      , f (LazyText.pack "a") ~?= LazyByteString.pack [0x61]
-      ]
-    , "From LazyText ByteString" ~:
-      let f = Witch.from @LazyText.Text @ByteString.ByteString in
-      [ f (LazyText.pack "") ~?= ByteString.pack []
-      , f (LazyText.pack "a") ~?= ByteString.pack [0x61]
-      ]
-
-    -- String
-
-    , "From String Text" ~:
-      let f = Witch.from @String @Text.Text in
-      [ f "" ~?= Text.pack ""
-      , f "a" ~?= Text.pack "a"
-      , f "ab" ~?= Text.pack "ab"
-      ]
-    , "From Text String" ~:
-      let f = Witch.from @Text.Text @String in
-      [ f (Text.pack "") ~?= ""
-      , f (Text.pack "a") ~?= "a"
-      , f (Text.pack "ab") ~?= "ab"
-      ]
-    , "From String LazyText" ~:
-      let f = Witch.from @String @LazyText.Text in
-      [ f "" ~?= LazyText.pack ""
-      , f "a" ~?= LazyText.pack "a"
-      , f "ab" ~?= LazyText.pack "ab"
-      ]
-    , "From LazyText String" ~:
-      let f = Witch.from @LazyText.Text @String in
-      [ f (LazyText.pack "") ~?= ""
-      , f (LazyText.pack "a") ~?= "a"
-      , f (LazyText.pack "ab") ~?= "ab"
-      ]
-    , "From String ByteString" ~:
-      let f = Witch.from @String @ByteString.ByteString in
-      [ f "" ~?= ByteString.pack []
-      , f "a" ~?= ByteString.pack [0x61]
-      ]
-    , "From String LazyByteString" ~:
-      let f = Witch.from @String @LazyByteString.ByteString in
-      [ f "" ~?= LazyByteString.pack []
-      , f "a" ~?= LazyByteString.pack [0x61]
-      ]
-
-    -- Day
-
-    , "From Integer Day" ~:
-      let f = Witch.from @Integer @Time.Day in
-      [ f 0 ~?= Time.ModifiedJulianDay 0
-      ]
-    , "From Day Integer" ~:
-      let f = Witch.from @Time.Day @Integer in
-      [ f (Time.ModifiedJulianDay 0) ~?= 0
-      ]
-
-    -- DayOfWeek
-
-    , "From Day DayOfWeek" ~:
-      let f = Witch.from @Time.Day @Time.DayOfWeek in
-      [ f (Time.ModifiedJulianDay 0) ~?= Time.Wednesday
-      ]
-
-    -- UniversalTime
-
-    , "From Rational UniversalTime" ~:
-      let f = Witch.from @Rational @Time.UniversalTime in
-      [ f 0 ~?= Time.ModJulianDate 0
-      ]
-    , "From UniversalTime Rational" ~:
-      let f = Witch.from @Time.UniversalTime @Rational in
-      [ f (Time.ModJulianDate 0) ~?= 0
-      ]
-
-    -- DiffTime
-
-    , "From Pico DiffTime" ~:
-      let f = Witch.from @Fixed.Pico @Time.DiffTime in
-      [ f 0 ~?= 0
-      ]
-    , "From DiffTime Pico" ~:
-      let f = Witch.from @Time.DiffTime @Fixed.Pico in
-      [ f 0 ~?= 0
-      ]
-
-    -- NominalDiffTime
-
-    , "From Pico NominalDiffTime" ~:
-      let f = Witch.from @Fixed.Pico @Time.NominalDiffTime in
-      [ f 0 ~?= 0
-      ]
-    , "From NominalDiffTime Pico" ~:
-      let f = Witch.from @Time.NominalDiffTime @Fixed.Pico in
-      [ f 0 ~?= 0
-      ]
-
-    -- POSIXTime
-
-    , "From SystemTime POSIXTime" ~:
-      let f = Witch.from @Time.SystemTime @Time.POSIXTime in
-      [ f (Time.MkSystemTime 0 0) ~?= 0
-      ]
-    , "From UTCTime POSIXTime" ~:
-      let f = Witch.from @Time.UTCTime @Time.POSIXTime in
-      [ f unixEpoch ~?= 0
-      ]
-    , "From POSIXTime UTCTime" ~:
-      let f = Witch.from @Time.POSIXTime @Time.UTCTime in
-      [ f 0 ~?= unixEpoch
-      ]
-
-    -- SystemTime
-
-    , "From UTCTime SystemTime" ~:
-      let f = Witch.from @Time.UTCTime @Time.SystemTime in
-      [ f unixEpoch ~?= Time.MkSystemTime 0 0
-      ]
-    , "From SystemTime AbsoluteTime" ~:
-      let f = Witch.from @Time.SystemTime @Time.AbsoluteTime in
-      [ f (Time.MkSystemTime (-3506716800) 0) ~?= Time.taiEpoch
-      ]
-    , "From SystemTime UTCTime" ~:
-      let f = Witch.from @Time.SystemTime @Time.UTCTime in
-      [ f (Time.MkSystemTime 0 0) ~?= unixEpoch
-      ]
-
-    -- TimeOfDay
-
-    , "From DiffTime TimeOfDay" ~:
-      let f = Witch.from @Time.DiffTime @Time.TimeOfDay in
-      [ f 0 ~?= Time.TimeOfDay 0 0 0
-      ]
-    , "From Rational TimeOfDay" ~:
-      let f = Witch.from @Rational @Time.TimeOfDay in
-      [ f 0 ~?= Time.TimeOfDay 0 0 0
-      ]
-    , "From TimeOfDay DiffTime" ~:
-      let f = Witch.from @Time.TimeOfDay @Time.DiffTime in
-      [ f (Time.TimeOfDay 0 0 0) ~?= 0
-      ]
-    , "From TimeOfDay Rational" ~:
-      let f = Witch.from @Time.TimeOfDay @Rational in
-      [ f (Time.TimeOfDay 0 0 0) ~?= 0
-      ]
-
-    -- CalendarDiffTime
-
-    , "From CalendarDiffDays CalendarDiffTime" ~:
-      let f = Witch.from @Time.CalendarDiffDays @Time.CalendarDiffTime in
-      [ f (Time.CalendarDiffDays 0 0) ~?= Time.CalendarDiffTime 0 0
-      ]
-    , "From NominalDiffTime CalendarDiffTime" ~:
-      let f = Witch.from @Time.NominalDiffTime @Time.CalendarDiffTime in
-      [ f 0 ~?= Time.CalendarDiffTime 0 0
-      ]
-
-    -- ZonedTime
-
-    , "From ZonedTime UTCTime" ~:
-      let f = Witch.from @Time.ZonedTime @Time.UTCTime in
-      [ f (Time.ZonedTime (Time.LocalTime (Time.ModifiedJulianDay 0) (Time.TimeOfDay 0 0 0)) Time.utc) ~?= Time.UTCTime (Time.ModifiedJulianDay 0) 0
-      ]
-    ]
-  ]
+main =
+  runTestTTAndExit
+    $ "Witch"
+    ~: [ "From" ~: ["from" ~: [Witch.from (1 :: Int.Int8) ~?= (1 :: Int.Int16)]]
+       , "TryFrom"
+         ~: [ "tryFrom"
+                ~: let f = hush . Witch.tryFrom @Int.Int16 @Int.Int8
+                   in [f 1 ~?= Just 1, f 128 ~?= Nothing]
+            ]
+       , "Utility"
+         ~: [ "as" ~: [Witch.as @Int.Int8 1 ~?= 1]
+            , "from" ~: [Witch.from @Int.Int8 1 ~?= (1 :: Int.Int16)]
+            , "into" ~: [Witch.into @Int.Int16 (1 :: Int.Int8) ~?= 1]
+            , "over" ~: [Witch.over @Int.Int8 (+ 1) (Age 1) ~?= Age 2]
+            , "via"
+              ~: [Witch.via @Int.Int16 (1 :: Int.Int8) ~?= (1 :: Int.Int32)]
+            , "tryFrom"
+              ~: [hush (Witch.tryFrom @Int.Int16 1) ~?= Just (1 :: Int.Int8)]
+            , "tryInto"
+              ~: [hush (Witch.tryInto @Int.Int8 (1 :: Int.Int16)) ~?= Just 1]
+            , "tryVia"
+              ~: let f = Witch.tryVia @Int.Int16 @Int.Int32 @Int.Int8
+                 in
+                   [ hush (f 1) ~?= Just 1
+                   , hush (f 128) ~?= Nothing
+                   , hush (f 32768) ~?= Nothing
+                   ]
+            , "unsafeFrom"
+              ~: let f = Witch.unsafeFrom @Int.Int16 @Int.Int8
+                 in
+                   [ f 1 ~?= 1
+                   , TestCase $ do
+                     result <-
+                       Exception.try @Exception.SomeException
+                       . Exception.evaluate
+                       $ f 128
+                     assertBool (show result) $ Either.isLeft result
+                   ]
+            , "unsafeInto"
+              ~: [Witch.unsafeInto @Int.Int8 (1 :: Int.Int16) ~?= 1]
+            ]
+       , "Lift"
+         ~: [ "liftedFrom"
+              ~: [($$(Witch.liftedFrom (1 :: Int.Int16)) :: Int.Int8) ~?= 1]
+            , "liftedInto"
+              ~: [$$(Witch.liftedInto @Int.Int8 (1 :: Int.Int16)) ~?= 1]
+            ]
+       , "TryFromException"
+         ~: [ "show"
+                ~: [ show (Witch.TryFromException @Int @Int 0 Nothing)
+                     ~?= "TryFromException @Int @Int 0 Nothing"
+                   , show
+                       (Witch.TryFromException @(Seq.Seq Int) @(Seq.Seq Int)
+                         (Seq.fromList [])
+                         (Just (Exception.toException Exception.Overflow))
+                       )
+                     ~?= "TryFromException @(Seq Int) @(Seq Int) (fromList []) (Just arithmetic overflow)"
+                   ]
+            ]
+       , "Instances"
+         ~: [ "From a a" ~: let f = Witch.from @Int @Int in [f 0 ~?= 0]
+
+    -- Int8
+            , "From Int8 Int16"
+              ~: let f = Witch.from @Int.Int8 @Int.Int16
+                 in [f 0 ~?= 0, f 127 ~?= 127, f (-128) ~?= (-128)]
+            , "From Int8 Int32"
+              ~: let f = Witch.from @Int.Int8 @Int.Int32
+                 in [f 0 ~?= 0, f 127 ~?= 127, f (-128) ~?= (-128)]
+            , "From Int8 Int64"
+              ~: let f = Witch.from @Int.Int8 @Int.Int64
+                 in [f 0 ~?= 0, f 127 ~?= 127, f (-128) ~?= (-128)]
+            , "From Int8 Int"
+              ~: let f = Witch.from @Int.Int8 @Int
+                 in [f 0 ~?= 0, f 127 ~?= 127, f (-128) ~?= (-128)]
+            , "From Int8 Integer"
+              ~: let f = Witch.from @Int.Int8 @Integer
+                 in [f 0 ~?= 0, f 127 ~?= 127, f (-128) ~?= (-128)]
+            , "TryFrom Int8 Word8"
+              ~: let f = hush . Witch.tryFrom @Int.Int8 @Word.Word8
+                 in [f 0 ~?= Just 0, f 127 ~?= Just 127, f (-1) ~?= Nothing]
+            , "TryFrom Int8 Word16"
+              ~: let f = hush . Witch.tryFrom @Int.Int8 @Word.Word16
+                 in [f 0 ~?= Just 0, f 127 ~?= Just 127, f (-1) ~?= Nothing]
+            , "TryFrom Int8 Word32"
+              ~: let f = hush . Witch.tryFrom @Int.Int8 @Word.Word32
+                 in [f 0 ~?= Just 0, f 127 ~?= Just 127, f (-1) ~?= Nothing]
+            , "TryFrom Int8 Word64"
+              ~: let f = hush . Witch.tryFrom @Int.Int8 @Word.Word64
+                 in [f 0 ~?= Just 0, f 127 ~?= Just 127, f (-1) ~?= Nothing]
+            , "TryFrom Int8 Word"
+              ~: let f = hush . Witch.tryFrom @Int.Int8 @Word
+                 in [f 0 ~?= Just 0, f 127 ~?= Just 127, f (-1) ~?= Nothing]
+            , "TryFrom Int8 Natural"
+              ~: let f = hush . Witch.tryFrom @Int.Int8 @Natural.Natural
+                 in [f 0 ~?= Just 0, f 127 ~?= Just 127, f (-1) ~?= Nothing]
+            , "From Int8 Float"
+              ~: let f = Witch.from @Int.Int8 @Float
+                 in [f 0 ~?= 0, f 127 ~?= 127, f (-128) ~?= (-128)]
+            , "From Int8 Double"
+              ~: let f = Witch.from @Int.Int8 @Double
+                 in [f 0 ~?= 0, f 127 ~?= 127, f (-128) ~?= (-128)]
+
+    -- Int16
+            , "TryFrom Int16 Int8"
+              ~: let f = hush . Witch.tryFrom @Int.Int16 @Int.Int8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 127 ~?= Just 127
+                   , f 128 ~?= Nothing
+                   , f (-128) ~?= Just (-128)
+                   , f (-129) ~?= Nothing
+                   ]
+            , "From Int16 Int32"
+              ~: let f = Witch.from @Int.Int16 @Int.Int32
+                 in [f 0 ~?= 0, f 32767 ~?= 32767, f (-32768) ~?= (-32768)]
+            , "From Int16 Int64"
+              ~: let f = Witch.from @Int.Int16 @Int.Int64
+                 in [f 0 ~?= 0, f 32767 ~?= 32767, f (-32768) ~?= (-32768)]
+            , "From Int16 Int"
+              ~: let f = Witch.from @Int.Int16 @Int
+                 in [f 0 ~?= 0, f 32767 ~?= 32767, f (-32768) ~?= (-32768)]
+            , "From Int16 Integer"
+              ~: let f = Witch.from @Int.Int16 @Integer
+                 in [f 0 ~?= 0, f 32767 ~?= 32767, f (-32768) ~?= (-32768)]
+            , "TryFrom Int16 Word8"
+              ~: let f = hush . Witch.tryFrom @Int.Int16 @Word.Word8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 255 ~?= Just 255
+                   , f 256 ~?= Nothing
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int16 Word16"
+              ~: let f = hush . Witch.tryFrom @Int.Int16 @Word.Word16
+                 in [f 0 ~?= Just 0, f 127 ~?= Just 127, f (-1) ~?= Nothing]
+            , "TryFrom Int16 Word32"
+              ~: let f = hush . Witch.tryFrom @Int.Int16 @Word.Word32
+                 in [f 0 ~?= Just 0, f 32767 ~?= Just 32767, f (-1) ~?= Nothing]
+            , "TryFrom Int16 Word64"
+              ~: let f = hush . Witch.tryFrom @Int.Int16 @Word.Word64
+                 in [f 0 ~?= Just 0, f 32767 ~?= Just 32767, f (-1) ~?= Nothing]
+            , "TryFrom Int16 Word"
+              ~: let f = hush . Witch.tryFrom @Int.Int16 @Word
+                 in [f 0 ~?= Just 0, f 32767 ~?= Just 32767, f (-1) ~?= Nothing]
+            , "TryFrom Int16 Natural"
+              ~: let f = hush . Witch.tryFrom @Int.Int16 @Natural.Natural
+                 in [f 0 ~?= Just 0, f 32767 ~?= Just 32767, f (-1) ~?= Nothing]
+            , "From Int16 Float"
+              ~: let f = Witch.from @Int.Int16 @Float
+                 in [f 0 ~?= 0, f 32767 ~?= 32767, f (-32768) ~?= (-32768)]
+            , "From Int16 Double"
+              ~: let f = Witch.from @Int.Int16 @Double
+                 in [f 0 ~?= 0, f 32767 ~?= 32767, f (-32768) ~?= (-32768)]
+
+    -- Int32
+            , "TryFrom Int32 Int8"
+              ~: let f = hush . Witch.tryFrom @Int.Int32 @Int.Int8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 127 ~?= Just 127
+                   , f 128 ~?= Nothing
+                   , f (-128) ~?= Just (-128)
+                   , f (-129) ~?= Nothing
+                   ]
+            , "TryFrom Int32 Int16"
+              ~: let f = hush . Witch.tryFrom @Int.Int32 @Int.Int16
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 32767 ~?= Just 32767
+                   , f 32768 ~?= Nothing
+                   , f (-32768) ~?= Just (-32768)
+                   , f (-32769) ~?= Nothing
+                   ]
+            , "From Int32 Int64"
+              ~: let f = Witch.from @Int.Int32 @Int.Int64
+                 in
+                   [ f 0 ~?= 0
+                   , f 2147483647 ~?= 2147483647
+                   , f (-2147483648) ~?= (-2147483648)
+                   ]
+            , "TryFrom Int32 Int"
+              ~: let f = hush . Witch.tryFrom @Int.Int32 @Int
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , f (-2147483648) ~?= Just (-2147483648)
+                   ]
+            , "From Int32 Integer"
+              ~: let f = Witch.from @Int.Int32 @Integer
+                 in
+                   [ f 0 ~?= 0
+                   , f 2147483647 ~?= 2147483647
+                   , f (-2147483648) ~?= (-2147483648)
+                   ]
+            , "TryFrom Int32 Word8"
+              ~: let f = hush . Witch.tryFrom @Int.Int32 @Word.Word8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 255 ~?= Just 255
+                   , f 256 ~?= Nothing
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int32 Word16"
+              ~: let f = hush . Witch.tryFrom @Int.Int32 @Word.Word16
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 65535 ~?= Just 65535
+                   , f 65536 ~?= Nothing
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int32 Word32"
+              ~: let f = hush . Witch.tryFrom @Int.Int32 @Word.Word32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int32 Word64"
+              ~: let f = hush . Witch.tryFrom @Int.Int32 @Word.Word64
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int32 Word"
+              ~: let f = hush . Witch.tryFrom @Int.Int32 @Word
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int32 Natural"
+              ~: let f = hush . Witch.tryFrom @Int.Int32 @Natural.Natural
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int32 Float"
+              ~: let f = hush . Witch.tryFrom @Int.Int32 @Float
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   , f (-16777215) ~?= Just (-16777215)
+                   , f (-16777216) ~?= Nothing
+                   ]
+            , "From Int32 Double"
+              ~: let f = Witch.from @Int.Int32 @Double
+                 in
+                   [ f 0 ~?= 0
+                   , f 2147483647 ~?= 2147483647
+                   , f (-2147483648) ~?= (-2147483648)
+                   ]
+
+    -- Int64
+            , "TryFrom Int64 Int8"
+              ~: let f = hush . Witch.tryFrom @Int.Int64 @Int.Int8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 127 ~?= Just 127
+                   , f 128 ~?= Nothing
+                   , f (-128) ~?= Just (-128)
+                   , f (-129) ~?= Nothing
+                   ]
+            , "TryFrom Int64 Int16"
+              ~: let f = hush . Witch.tryFrom @Int.Int64 @Int.Int16
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 32767 ~?= Just 32767
+                   , f 32768 ~?= Nothing
+                   , f (-32768) ~?= Just (-32768)
+                   , f (-32769) ~?= Nothing
+                   ]
+            , "TryFrom Int64 Int32"
+              ~: let f = hush . Witch.tryFrom @Int.Int64 @Int.Int32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , f 2147483648 ~?= Nothing
+                   , f (-2147483648) ~?= Just (-2147483648)
+                   , f (-2147483649) ~?= Nothing
+                   ]
+            , "TryFrom Int64 Int"
+              ~: let f = hush . Witch.tryFrom @Int.Int64 @Int
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Int
+                     in
+                       if toInteger x >= 9223372036854775807
+                         then f 9223372036854775807 ~?= Just 9223372036854775807
+                         else f (fromIntegral x) ~?= Just x
+                   , let x = minBound :: Int
+                     in
+                       if toInteger x <= (-9223372036854775808)
+                         then f (-9223372036854775808)
+                           ~?= Just (-9223372036854775808)
+                         else f (fromIntegral x) ~?= Just x
+                   ]
+            , "From Int64 Integer"
+              ~: let f = Witch.from @Int.Int64 @Integer
+                 in
+                   [ f 0 ~?= 0
+                   , f 9223372036854775807 ~?= 9223372036854775807
+                   , f (-9223372036854775808) ~?= (-9223372036854775808)
+                   ]
+            , "TryFrom Int64 Word8"
+              ~: let f = hush . Witch.tryFrom @Int.Int64 @Word.Word8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 255 ~?= Just 255
+                   , f 256 ~?= Nothing
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int64 Word16"
+              ~: let f = hush . Witch.tryFrom @Int.Int64 @Word.Word16
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 65535 ~?= Just 65535
+                   , f 65536 ~?= Nothing
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int64 Word32"
+              ~: let f = hush . Witch.tryFrom @Int.Int64 @Word.Word32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int64 Word64"
+              ~: let f = hush . Witch.tryFrom @Int.Int64 @Word.Word64
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 9223372036854775807 ~?= Just 9223372036854775807
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int64 Word"
+              ~: let f = hush . Witch.tryFrom @Int.Int64 @Word
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Word
+                     in
+                       if toInteger x >= 9223372036854775807
+                         then f 9223372036854775807 ~?= Just 9223372036854775807
+                         else f (fromIntegral x) ~?= Just x
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int64 Natural"
+              ~: let f = hush . Witch.tryFrom @Int.Int64 @Natural.Natural
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 9223372036854775807 ~?= Just 9223372036854775807
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int64 Float"
+              ~: let f = hush . Witch.tryFrom @Int.Int64 @Float
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   , f (-16777215) ~?= Just (-16777215)
+                   , f (-16777216) ~?= Nothing
+                   ]
+            , "TryFrom Int64 Double"
+              ~: let f = hush . Witch.tryFrom @Int.Int64 @Double
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 9007199254740991 ~?= Just 9007199254740991
+                   , f 9007199254740992 ~?= Nothing
+                   , f (-9007199254740991) ~?= Just (-9007199254740991)
+                   , f (-9007199254740992) ~?= Nothing
+                   ]
+
+    -- Int
+            , "TryFrom Int Int8"
+              ~: let f = hush . Witch.tryFrom @Int @Int.Int8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 127 ~?= Just 127
+                   , f 128 ~?= Nothing
+                   , f (-128) ~?= Just (-128)
+                   , f (-129) ~?= Nothing
+                   ]
+            , "TryFrom Int Int16"
+              ~: let f = hush . Witch.tryFrom @Int @Int.Int16
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 32767 ~?= Just 32767
+                   , f 32768 ~?= Nothing
+                   , f (-32768) ~?= Just (-32768)
+                   , f (-32769) ~?= Nothing
+                   ]
+            , "TryFrom Int Int32"
+              ~: let f = hush . Witch.tryFrom @Int @Int.Int32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , let x = maxBound :: Int
+                     in
+                       if toInteger x >= 2147483648
+                         then f 2147483648 ~?= Nothing
+                         else f x ~?= Just (fromIntegral x)
+                   , f (-2147483648) ~?= Just (-2147483648)
+                   , let x = minBound :: Int
+                     in
+                       if toInteger x <= (-2147483649)
+                         then f (-2147483649) ~?= Nothing
+                         else f x ~?= Just (fromIntegral x)
+                   ]
+            , "From Int Int64"
+              ~: let f = Witch.from @Int @Int.Int64
+                 in
+                   [ f 0 ~?= 0
+                   , f maxBound ~?= fromIntegral (maxBound :: Int)
+                   , f minBound ~?= fromIntegral (minBound :: Int)
+                   ]
+            , "From Int Integer"
+              ~: let f = Witch.from @Int @Integer
+                 in
+                   [ f 0 ~?= 0
+                   , f maxBound ~?= fromIntegral (maxBound :: Int)
+                   , f minBound ~?= fromIntegral (minBound :: Int)
+                   ]
+            , "TryFrom Int Word8"
+              ~: let f = hush . Witch.tryFrom @Int @Word.Word8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 255 ~?= Just 255
+                   , f 256 ~?= Nothing
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int Word16"
+              ~: let f = hush . Witch.tryFrom @Int @Word.Word16
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 65535 ~?= Just 65535
+                   , f 65536 ~?= Nothing
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int Word32"
+              ~: let f = hush . Witch.tryFrom @Int @Word.Word32
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Int
+                     in
+                       if toInteger x >= 4294967295
+                         then f 4294967295 ~?= Just 4294967295
+                         else f x ~?= Just (fromIntegral x)
+                   , let x = maxBound :: Int
+                     in
+                       if toInteger x >= 4294967296
+                         then f 4294967296 ~?= Nothing
+                         else f x ~?= Just (fromIntegral x)
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int Word64"
+              ~: let f = hush . Witch.tryFrom @Int @Word.Word64
+                 in
+                   [ f 0 ~?= Just 0
+                   , f maxBound ~?= Just (fromIntegral (maxBound :: Int))
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int Word"
+              ~: let f = hush . Witch.tryFrom @Int @Word
+                 in
+                   [ f 0 ~?= Just 0
+                   , f maxBound ~?= Just (fromIntegral (maxBound :: Int))
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int Natural"
+              ~: let f = hush . Witch.tryFrom @Int @Natural.Natural
+                 in
+                   [ f 0 ~?= Just 0
+                   , f maxBound ~?= Just (fromIntegral (maxBound :: Int))
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Int Float"
+              ~: let f = hush . Witch.tryFrom @Int @Float
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   , f (-16777215) ~?= Just (-16777215)
+                   , f (-16777216) ~?= Nothing
+                   ]
+            , "TryFrom Int Double"
+              ~: let f = hush . Witch.tryFrom @Int @Double
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Int
+                     in
+                       if toInteger x >= 9007199254740991
+                         then f 9007199254740991 ~?= Just 9007199254740991
+                         else f x ~?= Just (fromIntegral x)
+                   , let x = maxBound :: Int
+                     in
+                       if toInteger x >= 9007199254740992
+                         then f 9007199254740992 ~?= Nothing
+                         else f x ~?= Just (fromIntegral x)
+                   , let x = minBound :: Int
+                     in
+                       if toInteger x <= (-9007199254740991)
+                         then f (-9007199254740991) ~?= Just (-9007199254740991)
+                         else f x ~?= Just (fromIntegral x)
+                   , let x = minBound :: Int
+                     in
+                       if toInteger x <= (-9007199254740992)
+                         then f (-9007199254740992) ~?= Nothing
+                         else f x ~?= Just (fromIntegral x)
+                   ]
+
+    -- Integer
+            , "TryFrom Integer Int8"
+              ~: let f = hush . Witch.tryFrom @Integer @Int.Int8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 127 ~?= Just 127
+                   , f 128 ~?= Nothing
+                   , f (-128) ~?= Just (-128)
+                   , f (-129) ~?= Nothing
+                   ]
+            , "TryFrom Integer Int16"
+              ~: let f = hush . Witch.tryFrom @Integer @Int.Int16
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 32767 ~?= Just 32767
+                   , f 32768 ~?= Nothing
+                   , f (-32768) ~?= Just (-32768)
+                   , f (-32769) ~?= Nothing
+                   ]
+            , "TryFrom Integer Int32"
+              ~: let f = hush . Witch.tryFrom @Integer @Int.Int32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , f 2147483648 ~?= Nothing
+                   , f (-2147483648) ~?= Just (-2147483648)
+                   , f (-2147483649) ~?= Nothing
+                   ]
+            , "TryFrom Integer Int64"
+              ~: let f = hush . Witch.tryFrom @Integer @Int.Int64
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 9223372036854775807 ~?= Just 9223372036854775807
+                   , f 9223372036854775808 ~?= Nothing
+                   , f (-9223372036854775808) ~?= Just (-9223372036854775808)
+                   , f (-9223372036854775809) ~?= Nothing
+                   ]
+            , "TryFrom Integer Int"
+              ~: let f = hush . Witch.tryFrom @Integer @Int
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Int in f (fromIntegral x) ~?= Just x
+                   , let x = toInteger (maxBound :: Int) + 1 in f x ~?= Nothing
+                   , let x = minBound :: Int in f (fromIntegral x) ~?= Just x
+                   , let x = toInteger (minBound :: Int) - 1 in f x ~?= Nothing
+                   ]
+            , "TryFrom Integer Word8"
+              ~: let f = hush . Witch.tryFrom @Integer @Word.Word8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 255 ~?= Just 255
+                   , f 256 ~?= Nothing
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Integer Word16"
+              ~: let f = hush . Witch.tryFrom @Integer @Word.Word16
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 65535 ~?= Just 65535
+                   , f 65536 ~?= Nothing
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Integer Word32"
+              ~: let f = hush . Witch.tryFrom @Integer @Word.Word32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 4294967295 ~?= Just 4294967295
+                   , f 4294967296 ~?= Nothing
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Integer Word64"
+              ~: let f = hush . Witch.tryFrom @Integer @Word.Word64
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 18446744073709551615 ~?= Just 18446744073709551615
+                   , f 18446744073709551616 ~?= Nothing
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Integer Word"
+              ~: let f = hush . Witch.tryFrom @Integer @Word
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Word in f (fromIntegral x) ~?= Just x
+                   , let x = toInteger (maxBound :: Word) + 1
+                     in f x ~?= Nothing
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Integer Natural"
+              ~: let f = hush . Witch.tryFrom @Integer @Natural.Natural
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 18446744073709551616 ~?= Just 18446744073709551616
+                   , f (-1) ~?= Nothing
+                   ]
+            , "TryFrom Integer Float"
+              ~: let f = hush . Witch.tryFrom @Integer @Float
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   , f (-16777215) ~?= Just (-16777215)
+                   , f (-16777216) ~?= Nothing
+                   ]
+            , "TryFrom Integer Double"
+              ~: let f = hush . Witch.tryFrom @Integer @Double
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 9007199254740991 ~?= Just 9007199254740991
+                   , f 9007199254740992 ~?= Nothing
+                   , f (-9007199254740991) ~?= Just (-9007199254740991)
+                   , f (-9007199254740992) ~?= Nothing
+                   ]
+
+    -- Word8
+            , "From Word8 Word16"
+              ~: let f = Witch.from @Word.Word8 @Word.Word16
+                 in [f 0 ~?= 0, f 255 ~?= 255]
+            , "From Word8 Word32"
+              ~: let f = Witch.from @Word.Word8 @Word.Word32
+                 in [f 0 ~?= 0, f 255 ~?= 255]
+            , "From Word8 Word64"
+              ~: let f = Witch.from @Word.Word8 @Word.Word64
+                 in [f 0 ~?= 0, f 255 ~?= 255]
+            , "From Word8 Word"
+              ~: let f = Witch.from @Word.Word8 @Word
+                 in [f 0 ~?= 0, f 255 ~?= 255]
+            , "From Word8 Natural"
+              ~: let f = Witch.from @Word.Word8 @Natural.Natural
+                 in [f 0 ~?= 0, f 255 ~?= 255]
+            , "TryFrom Word8 Int8"
+              ~: let f = hush . Witch.tryFrom @Word.Word8 @Int.Int8
+                 in [f 0 ~?= Just 0, f 127 ~?= Just 127, f 128 ~?= Nothing]
+            , "From Word8 Int16"
+              ~: let f = Witch.from @Word.Word8 @Int.Int16
+                 in [f 0 ~?= 0, f 255 ~?= 255]
+            , "From Word8 Int32"
+              ~: let f = Witch.from @Word.Word8 @Int.Int32
+                 in [f 0 ~?= 0, f 255 ~?= 255]
+            , "From Word8 Int64"
+              ~: let f = Witch.from @Word.Word8 @Int.Int64
+                 in [f 0 ~?= 0, f 255 ~?= 255]
+            , "From Word8 Int"
+              ~: let f = Witch.from @Word.Word8 @Int
+                 in [f 0 ~?= 0, f 255 ~?= 255]
+            , "From Word8 Integer"
+              ~: let f = Witch.from @Word.Word8 @Integer
+                 in [f 0 ~?= 0, f 255 ~?= 255]
+            , "From Word8 Float"
+              ~: let f = Witch.from @Word.Word8 @Float
+                 in [f 0 ~?= 0, f 255 ~?= 255]
+            , "From Word8 Double"
+              ~: let f = Witch.from @Word.Word8 @Double
+                 in [f 0 ~?= 0, f 255 ~?= 255]
+
+    -- Word16
+            , "TryFrom Word16 Word8"
+              ~: let f = hush . Witch.tryFrom @Word.Word16 @Word.Word8
+                 in [f 0 ~?= Just 0, f 255 ~?= Just 255, f 256 ~?= Nothing]
+            , "From Word16 Word32"
+              ~: let f = Witch.from @Word.Word16 @Word.Word32
+                 in [f 0 ~?= 0, f 65535 ~?= 65535]
+            , "From Word16 Word64"
+              ~: let f = Witch.from @Word.Word16 @Word.Word64
+                 in [f 0 ~?= 0, f 65535 ~?= 65535]
+            , "From Word16 Word"
+              ~: let f = Witch.from @Word.Word16 @Word
+                 in [f 0 ~?= 0, f 65535 ~?= 65535]
+            , "From Word16 Natural"
+              ~: let f = Witch.from @Word.Word16 @Natural.Natural
+                 in [f 0 ~?= 0, f 65535 ~?= 65535]
+            , "TryFrom Word16 Int8"
+              ~: let f = hush . Witch.tryFrom @Word.Word16 @Int.Int8
+                 in [f 0 ~?= Just 0, f 127 ~?= Just 127, f 128 ~?= Nothing]
+            , "TryFrom Word16 Int16"
+              ~: let f = hush . Witch.tryFrom @Word.Word16 @Int.Int16
+                 in
+                   [f 0 ~?= Just 0, f 32767 ~?= Just 32767, f 32768 ~?= Nothing]
+            , "From Word16 Int32"
+              ~: let f = Witch.from @Word.Word16 @Int.Int32
+                 in [f 0 ~?= 0, f 65535 ~?= 65535]
+            , "From Word16 Int64"
+              ~: let f = Witch.from @Word.Word16 @Int.Int64
+                 in [f 0 ~?= 0, f 65535 ~?= 65535]
+            , "From Word16 Int"
+              ~: let f = Witch.from @Word.Word16 @Int
+                 in [f 0 ~?= 0, f 65535 ~?= 65535]
+            , "From Word16 Integer"
+              ~: let f = Witch.from @Word.Word16 @Integer
+                 in [f 0 ~?= 0, f 65535 ~?= 65535]
+            , "From Word16 Float"
+              ~: let f = Witch.from @Word.Word16 @Float
+                 in [f 0 ~?= 0, f 65535 ~?= 65535]
+            , "From Word16 Double"
+              ~: let f = Witch.from @Word.Word16 @Double
+                 in [f 0 ~?= 0, f 65535 ~?= 65535]
+
+    -- Word32
+            , "TryFrom Word32 Word8"
+              ~: let f = hush . Witch.tryFrom @Word.Word32 @Word.Word8
+                 in [f 0 ~?= Just 0, f 255 ~?= Just 255, f 256 ~?= Nothing]
+            , "TryFrom Word32 Word16"
+              ~: let f = hush . Witch.tryFrom @Word.Word32 @Word.Word16
+                 in
+                   [f 0 ~?= Just 0, f 65535 ~?= Just 65535, f 65536 ~?= Nothing]
+            , "From Word32 Word64"
+              ~: let f = Witch.from @Word.Word32 @Word.Word64
+                 in [f 0 ~?= 0, f 4294967295 ~?= 4294967295]
+            , "TryFrom Word32 Word"
+              ~: let f = hush . Witch.tryFrom @Word.Word32 @Word
+                 in [f 0 ~?= Just 0, f 4294967295 ~?= Just 4294967295]
+            , "From Word32 Natural"
+              ~: let f = Witch.from @Word.Word32 @Natural.Natural
+                 in [f 0 ~?= 0, f 4294967295 ~?= 4294967295]
+            , "TryFrom Word32 Int8"
+              ~: let f = hush . Witch.tryFrom @Word.Word32 @Int.Int8
+                 in [f 0 ~?= Just 0, f 127 ~?= Just 127, f 128 ~?= Nothing]
+            , "TryFrom Word32 Int16"
+              ~: let f = hush . Witch.tryFrom @Word.Word32 @Int.Int16
+                 in
+                   [f 0 ~?= Just 0, f 32767 ~?= Just 32767, f 32768 ~?= Nothing]
+            , "TryFrom Word32 Int32"
+              ~: let f = hush . Witch.tryFrom @Word.Word32 @Int.Int32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , f 2147483648 ~?= Nothing
+                   ]
+            , "From Word32 Int64"
+              ~: let f = Witch.from @Word.Word32 @Int.Int64
+                 in [f 0 ~?= 0, f 4294967295 ~?= 4294967295]
+            , "TryFrom Word32 Int"
+              ~: let f = hush . Witch.tryFrom @Word.Word32 @Int
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Int
+                     in
+                       if toInteger x >= 4294967295
+                         then f 4294967295 ~?= Just 4294967295
+                         else f (fromIntegral x) ~?= Just x
+                   ]
+            , "From Word32 Integer"
+              ~: let f = Witch.from @Word.Word32 @Integer
+                 in [f 0 ~?= 0, f 4294967295 ~?= 4294967295]
+            , "TryFrom Word32 Float"
+              ~: let f = hush . Witch.tryFrom @Word.Word32 @Float
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   ]
+            , "From Word32 Double"
+              ~: let f = Witch.from @Word.Word32 @Double
+                 in [f 0 ~?= 0, f 4294967295 ~?= 4294967295]
+
+    -- Word64
+            , "TryFrom Word64 Word8"
+              ~: let f = hush . Witch.tryFrom @Word.Word64 @Word.Word8
+                 in [f 0 ~?= Just 0, f 255 ~?= Just 255, f 256 ~?= Nothing]
+            , "TryFrom Word64 Word16"
+              ~: let f = hush . Witch.tryFrom @Word.Word64 @Word.Word16
+                 in
+                   [f 0 ~?= Just 0, f 65535 ~?= Just 65535, f 65536 ~?= Nothing]
+            , "TryFrom Word64 Word32"
+              ~: let f = hush . Witch.tryFrom @Word.Word64 @Word.Word32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 4294967295 ~?= Just 4294967295
+                   , f 4294967296 ~?= Nothing
+                   ]
+            , "TryFrom Word64 Word"
+              ~: let f = hush . Witch.tryFrom @Word.Word64 @Word
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Word
+                     in
+                       if toInteger x >= 18446744073709551615
+                         then f 18446744073709551615
+                           ~?= Just 18446744073709551615
+                         else f (fromIntegral x) ~?= Just x
+                   ]
+            , "From Word64 Natural"
+              ~: let f = Witch.from @Word.Word64 @Natural.Natural
+                 in [f 0 ~?= 0, f 18446744073709551615 ~?= 18446744073709551615]
+            , "TryFrom Word64 Int8"
+              ~: let f = hush . Witch.tryFrom @Word.Word64 @Int.Int8
+                 in [f 0 ~?= Just 0, f 127 ~?= Just 127, f 128 ~?= Nothing]
+            , "TryFrom Word64 Int16"
+              ~: let f = hush . Witch.tryFrom @Word.Word64 @Int.Int16
+                 in
+                   [f 0 ~?= Just 0, f 32767 ~?= Just 32767, f 32768 ~?= Nothing]
+            , "TryFrom Word64 Int32"
+              ~: let f = hush . Witch.tryFrom @Word.Word64 @Int.Int32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , f 2147483648 ~?= Nothing
+                   ]
+            , "TryFrom Word64 Int64"
+              ~: let f = hush . Witch.tryFrom @Word.Word64 @Int.Int64
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 9223372036854775807 ~?= Just 9223372036854775807
+                   , f 9223372036854775808 ~?= Nothing
+                   ]
+            , "TryFrom Word64 Int"
+              ~: let f = hush . Witch.tryFrom @Word.Word64 @Int
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Int
+                     in
+                       hush (Witch.tryFrom @Word.Word64 @Int (fromIntegral x))
+                         ~?= Just x
+                   , let x = fromIntegral (maxBound :: Int) + 1 :: Word.Word64
+                     in hush (Witch.tryFrom @Word.Word64 @Int x) ~?= Nothing
+                   ]
+            , "From Word64 Integer"
+              ~: let f = Witch.from @Word.Word64 @Integer
+                 in [f 0 ~?= 0, f 18446744073709551615 ~?= 18446744073709551615]
+            , "TryFrom Word64 Float"
+              ~: let f = hush . Witch.tryFrom @Word.Word64 @Float
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   ]
+            , "TryFrom Word64 Double"
+              ~: let f = hush . Witch.tryFrom @Word.Word64 @Double
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 9007199254740991 ~?= Just 9007199254740991
+                   , f 9007199254740992 ~?= Nothing
+                   ]
+
+    -- Word
+            , "TryFrom Word Word8"
+              ~: let f = hush . Witch.tryFrom @Word @Word.Word8
+                 in [f 0 ~?= Just 0, f 255 ~?= Just 255, f 256 ~?= Nothing]
+            , "TryFrom Word Word16"
+              ~: let f = hush . Witch.tryFrom @Word @Word.Word16
+                 in
+                   [f 0 ~?= Just 0, f 65535 ~?= Just 65535, f 65536 ~?= Nothing]
+            , "TryFrom Word Word32"
+              ~: let f = hush . Witch.tryFrom @Word @Word.Word32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 4294967295 ~?= Just 4294967295
+                   , let x = maxBound :: Word
+                     in
+                       if toInteger x >= 4294967296
+                         then f 4294967296 ~?= Nothing
+                         else f x ~?= Just (fromIntegral x)
+                   ]
+            , "From Word Word64"
+              ~: let f = Witch.from @Word @Word.Word64
+                 in [f 0 ~?= 0, f maxBound ~?= fromIntegral (maxBound :: Word)]
+            , "From Word Natural"
+              ~: let f = Witch.from @Word @Natural.Natural
+                 in [f 0 ~?= 0, f maxBound ~?= fromIntegral (maxBound :: Word)]
+            , "TryFrom Word Int8"
+              ~: let f = hush . Witch.tryFrom @Word @Int.Int8
+                 in [f 0 ~?= Just 0, f 127 ~?= Just 127, f 128 ~?= Nothing]
+            , "TryFrom Word Int16"
+              ~: let f = hush . Witch.tryFrom @Word @Int.Int16
+                 in
+                   [f 0 ~?= Just 0, f 32767 ~?= Just 32767, f 32768 ~?= Nothing]
+            , "TryFrom Word Int32"
+              ~: let f = hush . Witch.tryFrom @Word @Int.Int32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , f 2147483648 ~?= Nothing
+                   ]
+            , "TryFrom Word Int64"
+              ~: let f = hush . Witch.tryFrom @Word @Int.Int64
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Word
+                     in
+                       if toInteger x >= 9223372036854775807
+                         then f 9223372036854775807 ~?= Just 9223372036854775807
+                         else f x ~?= Just (fromIntegral x)
+                   , let x = maxBound :: Word
+                     in
+                       if toInteger x >= 9223372036854775808
+                         then f 9223372036854775808 ~?= Nothing
+                         else f x ~?= Just (fromIntegral x)
+                   ]
+            , "TryFrom Word Int"
+              ~: let f = hush . Witch.tryFrom @Word @Int
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Int
+                     in
+                       hush (Witch.tryFrom @Word @Int (fromIntegral x))
+                         ~?= Just x
+                   , let x = fromIntegral (maxBound :: Int) + 1 :: Word
+                     in hush (Witch.tryFrom @Word @Int x) ~?= Nothing
+                   ]
+            , "From Word Integer"
+              ~: let f = Witch.from @Word @Integer
+                 in [f 0 ~?= 0, f maxBound ~?= fromIntegral (maxBound :: Word)]
+            , "TryFrom Word Float"
+              ~: let f = hush . Witch.tryFrom @Word @Float
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   ]
+            , "TryFrom Word Double"
+              ~: let f = hush . Witch.tryFrom @Word @Double
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Word
+                     in
+                       if toInteger x >= 9007199254740991
+                         then f 9007199254740991 ~?= Just 9007199254740991
+                         else f x ~?= Just (fromIntegral x)
+                   , let x = maxBound :: Word
+                     in
+                       if toInteger x >= 9007199254740992
+                         then f 9007199254740992 ~?= Nothing
+                         else f x ~?= Just (fromIntegral x)
+                   ]
+
+    -- Natural
+            , "TryFrom Natural Word8"
+              ~: let f = hush . Witch.tryFrom @Natural.Natural @Word.Word8
+                 in [f 0 ~?= Just 0, f 255 ~?= Just 255, f 256 ~?= Nothing]
+            , "TryFrom Natural Word16"
+              ~: let f = hush . Witch.tryFrom @Natural.Natural @Word.Word16
+                 in
+                   [f 0 ~?= Just 0, f 65535 ~?= Just 65535, f 65536 ~?= Nothing]
+            , "TryFrom Natural Word32"
+              ~: let f = hush . Witch.tryFrom @Natural.Natural @Word.Word32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 4294967295 ~?= Just 4294967295
+                   , f 4294967296 ~?= Nothing
+                   ]
+            , "TryFrom Natural Word64"
+              ~: let f = hush . Witch.tryFrom @Natural.Natural @Word.Word64
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 18446744073709551615 ~?= Just 18446744073709551615
+                   , f 18446744073709551616 ~?= Nothing
+                   ]
+            , "TryFrom Natural Word"
+              ~: let f = hush . Witch.tryFrom @Natural.Natural @Word
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Word
+                     in
+                       hush
+                           (Witch.tryFrom @Natural.Natural @Word
+                             (fromIntegral x)
+                           )
+                         ~?= Just x
+                   , let
+                       x =
+                         fromIntegral (maxBound :: Word) + 1 :: Natural.Natural
+                     in
+                       hush (Witch.tryFrom @Natural.Natural @Word x) ~?= Nothing
+                   ]
+            , "TryFrom Natural Int8"
+              ~: let f = hush . Witch.tryFrom @Natural.Natural @Int.Int8
+                 in [f 0 ~?= Just 0, f 127 ~?= Just 127, f 128 ~?= Nothing]
+            , "TryFrom Natural Int16"
+              ~: let f = hush . Witch.tryFrom @Natural.Natural @Int.Int16
+                 in
+                   [f 0 ~?= Just 0, f 32767 ~?= Just 32767, f 32768 ~?= Nothing]
+            , "TryFrom Natural Int32"
+              ~: let f = hush . Witch.tryFrom @Natural.Natural @Int.Int32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , f 2147483648 ~?= Nothing
+                   ]
+            , "TryFrom Natural Int64"
+              ~: let f = hush . Witch.tryFrom @Natural.Natural @Int.Int64
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 9223372036854775807 ~?= Just 9223372036854775807
+                   , f 9223372036854775808 ~?= Nothing
+                   ]
+            , "TryFrom Natural Int"
+              ~: let f = hush . Witch.tryFrom @Natural.Natural @Int
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Int
+                     in
+                       hush
+                           (Witch.tryFrom @Natural.Natural @Int (fromIntegral x)
+                           )
+                         ~?= Just x
+                   , let
+                       x =
+                         fromIntegral (maxBound :: Int) + 1 :: Natural.Natural
+                     in hush (Witch.tryFrom @Natural.Natural @Int x) ~?= Nothing
+                   ]
+            , "From Natural Integer"
+              ~: let f = Witch.from @Natural.Natural @Integer
+                 in [f 0 ~?= 0, f 9223372036854775808 ~?= 9223372036854775808]
+            , "TryFrom Natural Float"
+              ~: let f = hush . Witch.tryFrom @Natural.Natural @Float
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   ]
+            , "TryFrom Natural Double"
+              ~: let f = hush . Witch.tryFrom @Natural.Natural @Double
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 9007199254740991 ~?= Just 9007199254740991
+                   , f 9007199254740992 ~?= Nothing
+                   ]
+
+    -- Float
+            , "TryFrom Float Int8"
+              ~: let f = hush . Witch.tryFrom @Float @Int.Int8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 127 ~?= Just 127
+                   , f 128 ~?= Nothing
+                   , f (-128) ~?= Just (-128)
+                   , f (-129) ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Float Int16"
+              ~: let f = hush . Witch.tryFrom @Float @Int.Int16
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 32767 ~?= Just 32767
+                   , f 32768 ~?= Nothing
+                   , f (-32768) ~?= Just (-32768)
+                   , f (-32769) ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Float Int32"
+              ~: let f = hush . Witch.tryFrom @Float @Int.Int32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   , f (-16777215) ~?= Just (-16777215)
+                   , f (-16777216) ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Float Int64"
+              ~: let f = hush . Witch.tryFrom @Float @Int.Int64
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   , f (-16777215) ~?= Just (-16777215)
+                   , f (-16777216) ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Float Int"
+              ~: let f = hush . Witch.tryFrom @Float @Int
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   , f (-16777215) ~?= Just (-16777215)
+                   , f (-16777216) ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Float Integer"
+              ~: let f = hush . Witch.tryFrom @Float @Integer
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   , f (-16777215) ~?= Just (-16777215)
+                   , f (-16777216) ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Float Word8"
+              ~: let f = hush . Witch.tryFrom @Float @Word.Word8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 255 ~?= Just 255
+                   , f 256 ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Float Word16"
+              ~: let f = hush . Witch.tryFrom @Float @Word.Word16
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 65535 ~?= Just 65535
+                   , f 65536 ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Float Word32"
+              ~: let f = hush . Witch.tryFrom @Float @Word.Word32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Float Word64"
+              ~: let f = hush . Witch.tryFrom @Float @Word.Word64
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Float Word"
+              ~: let f = hush . Witch.tryFrom @Float @Word
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Float Natural"
+              ~: let f = hush . Witch.tryFrom @Float @Natural.Natural
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 16777215 ~?= Just 16777215
+                   , f 16777216 ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Float Rational"
+              ~: let f = hush . Witch.tryFrom @Float @Rational
+                 in
+                   [ f 0 ~?= Just 0
+                   , f (-0) ~?= Just 0
+                   , f 0.5 ~?= Just 0.5
+                   , f (-0.5) ~?= Just (-0.5)
+                   , f 16777215 ~?= Just 16777215
+                   , f (-16777215) ~?= Just (-16777215)
+                   , f 16777216 ~?= Just 16777216
+                   , f (-16777216) ~?= Just (-16777216)
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   , f 0.1 ~?= Just 0.1
+                   , f (-0.1) ~?= Just (-0.1)
+                   ]
+            , "From Float Double"
+              ~: let f = Witch.from @Float @Double
+                 in
+                   [ f 0 ~?= 0
+                   , f 0.5 ~?= 0.5
+                   , f (-0.5) ~?= (-0.5)
+                   , TestCase
+                     $ let x = f (0 / 0) in assertBool (show x) $ isNaN x
+                   , f (1 / 0) ~?= (1 / 0)
+                   , f (-1 / 0) ~?= (-1 / 0)
+                   ]
+
+    -- Double
+            , "TryFrom Double Int8"
+              ~: let f = hush . Witch.tryFrom @Double @Int.Int8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 127 ~?= Just 127
+                   , f 128 ~?= Nothing
+                   , f (-128) ~?= Just (-128)
+                   , f (-129) ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Double Int16"
+              ~: let f = hush . Witch.tryFrom @Double @Int.Int16
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 32767 ~?= Just 32767
+                   , f 32768 ~?= Nothing
+                   , f (-32768) ~?= Just (-32768)
+                   , f (-32769) ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Double Int32"
+              ~: let f = hush . Witch.tryFrom @Double @Int.Int32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 2147483647 ~?= Just 2147483647
+                   , f 2147483648 ~?= Nothing
+                   , f (-2147483648) ~?= Just (-2147483648)
+                   , f (-2147483649) ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Double Int64"
+              ~: let f = hush . Witch.tryFrom @Double @Int.Int64
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 9007199254740991 ~?= Just 9007199254740991
+                   , f 9007199254740992 ~?= Nothing
+                   , f (-9007199254740991) ~?= Just (-9007199254740991)
+                   , f (-9007199254740992) ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Double Int"
+              ~: let f = hush . Witch.tryFrom @Double @Int
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Int
+                     in
+                       if toInteger x >= 9007199254740991
+                         then f 9007199254740991 ~?= Just 9007199254740991
+                         else f (fromIntegral x) ~?= Just x
+                   , f 9007199254740992 ~?= Nothing
+                   , let x = minBound :: Int
+                     in
+                       if toInteger x <= (-9007199254740991)
+                         then f (-9007199254740991) ~?= Just (-9007199254740991)
+                         else f (fromIntegral x) ~?= Just x
+                   , f (-9007199254740992) ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Double Integer"
+              ~: let f = hush . Witch.tryFrom @Double @Integer
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 9007199254740991 ~?= Just 9007199254740991
+                   , f 9007199254740992 ~?= Nothing
+                   , f (-9007199254740991) ~?= Just (-9007199254740991)
+                   , f (-9007199254740992) ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Double Word8"
+              ~: let f = hush . Witch.tryFrom @Double @Word.Word8
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 255 ~?= Just 255
+                   , f 256 ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Double Word16"
+              ~: let f = hush . Witch.tryFrom @Double @Word.Word16
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 65535 ~?= Just 65535
+                   , f 65536 ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Double Word32"
+              ~: let f = hush . Witch.tryFrom @Double @Word.Word32
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 4294967295 ~?= Just 4294967295
+                   , f 4294967296 ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Double Word64"
+              ~: let f = hush . Witch.tryFrom @Double @Word.Word64
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 9007199254740991 ~?= Just 9007199254740991
+                   , f 9007199254740992 ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Double Word"
+              ~: let f = hush . Witch.tryFrom @Double @Word
+                 in
+                   [ f 0 ~?= Just 0
+                   , let x = maxBound :: Word
+                     in
+                       if toInteger x >= 9007199254740991
+                         then f 9007199254740991 ~?= Just 9007199254740991
+                         else f (fromIntegral x) ~?= Just x
+                   , f 9007199254740992 ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Double Natural"
+              ~: let f = hush . Witch.tryFrom @Double @Natural.Natural
+                 in
+                   [ f 0 ~?= Just 0
+                   , f 9007199254740991 ~?= Just 9007199254740991
+                   , f 9007199254740992 ~?= Nothing
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   ]
+            , "TryFrom Double Rational"
+              ~: let f = hush . Witch.tryFrom @Double @Rational
+                 in
+                   [ f 0 ~?= Just 0
+                   , f (-0) ~?= Just 0
+                   , f 0.5 ~?= Just 0.5
+                   , f (-0.5) ~?= Just (-0.5)
+                   , f 9007199254740991 ~?= Just 9007199254740991
+                   , f (-9007199254740991) ~?= Just (-9007199254740991)
+                   , f 9007199254740992 ~?= Just 9007199254740992
+                   , f (-9007199254740992) ~?= Just (-9007199254740992)
+                   , f (0 / 0) ~?= Nothing
+                   , f (1 / 0) ~?= Nothing
+                   , f (-1 / 0) ~?= Nothing
+                   , f 0.1 ~?= Just 0.1
+                   , f (-0.1) ~?= Just (-0.1)
+                   ]
+            , "From Double Float"
+              ~: let f = Witch.from @Double @Float
+                 in
+                   [ f 0 ~?= 0
+                   , f 0.5 ~?= 0.5
+                   , f (-0.5) ~?= (-0.5)
+                   , TestCase
+                     $ let x = f (0 / 0) in assertBool (show x) $ isNaN x
+                   , f (1 / 0) ~?= (1 / 0)
+                   , f (-1 / 0) ~?= (-1 / 0)
+                   ]
+
+    -- Ratio
+            , "From a (Ratio a)"
+              ~: let f = Witch.from @Int @(Ratio.Ratio Int)
+                 in [Witch.from @Integer @Rational 0 ~?= 0, f 0 ~?= 0]
+            , "TryFrom (Ratio a) a"
+              ~: let f = hush . Witch.tryFrom @(Ratio.Ratio Int) @Int
+                 in
+                   [ hush (Witch.tryFrom @Rational @Integer 0) ~?= Just 0
+                   , hush (Witch.tryFrom @Rational @Integer 0.5) ~?= Nothing
+                   , f 0 ~?= Just 0
+                   , f 0.5 ~?= Nothing
+                   ]
+            , "From Rational Float"
+              ~: let f = Witch.from @Rational @Float
+                 in
+                   [ f 0 ~?= 0
+                   , f 0.5 ~?= 0.5
+                   , f (-0.5) ~?= (-0.5)
+                   , f 0.1 ~?= 0.1
+                   , f (-0.1) ~?= (-0.1)
+                   ]
+            , "From Rational Double"
+              ~: let f = Witch.from @Rational @Double
+                 in
+                   [ f 0 ~?= 0
+                   , f 0.5 ~?= 0.5
+                   , f (-0.5) ~?= (-0.5)
+                   , f 0.1 ~?= 0.1
+                   , f (-0.1) ~?= (-0.1)
+                   ]
+            , "TryFrom Rational (Fixed a)"
+              ~: let f = hush . Witch.tryFrom @Rational @Fixed.Deci
+                 in
+                   [ hush (Witch.tryFrom @Rational @Fixed.Uni 1) ~?= Just 1
+                   , hush (Witch.tryFrom @Rational @Fixed.Uni 1.2) ~?= Nothing
+                   , f 0.1 ~?= Just 0.1
+                   , f 1.2 ~?= Just 1.2
+                   , f 12.3 ~?= Just 12.3
+                   , f 0.12 ~?= Nothing
+                   ]
+
+    -- Fixed
+            , "From Integer (Fixed a)"
+              ~: let f = Witch.from @Integer @Fixed.Deci
+                 in
+                   [ Witch.from @Integer @Fixed.Uni 1 ~?= 1
+                   , f 1 ~?= 0.1
+                   , f 10 ~?= 1
+                   , f 120 ~?= 12
+                   ]
+            , "From (Fixed a) Integer"
+              ~: let f = Witch.from @Fixed.Deci @Integer
+                 in
+                   [ Witch.from @Fixed.Uni @Integer 1 ~?= 1
+                   , f 0.1 ~?= 1
+                   , f 1 ~?= 10
+                   , f 12 ~?= 120
+                   ]
+            , "From (Fixed a) Rational"
+              ~: let f = Witch.from @Fixed.Deci @Rational
+                 in
+                   [ Witch.from @Fixed.Uni @Rational 1 ~?= 1
+                   , f 0.1 ~?= 0.1
+                   , f 1 ~?= 1
+                   , f 12 ~?= 12
+                   ]
+
+    -- Complex
+            , "From a (Complex a)"
+              ~: let f = Witch.from @Float @(Complex.Complex Float)
+                 in
+                   [ Witch.from @Double @(Complex.Complex Double) 1 ~?= 1
+                   , f 1 ~?= 1
+                   ]
+            , "TryFrom (Complex a) a"
+              ~: let f = hush . Witch.tryFrom @(Complex.Complex Float) @Float
+                 in
+                   [ hush (Witch.tryFrom @(Complex.Complex Double) @Double 1)
+                     ~?= Just 1
+                   , hush
+                       (Witch.tryFrom @(Complex.Complex Double) @Double
+                         (0 Complex.:+ 1)
+                       )
+                     ~?= Nothing
+                   , f 1 ~?= Just 1
+                   , f (0 Complex.:+ 1) ~?= Nothing
+                   ]
+
+    -- NonEmpty
+            , "TryFrom [a] (NonEmpty a)"
+              ~: let f = hush . Witch.tryFrom @[Int] @(NonEmpty.NonEmpty Int)
+                 in
+                   [ f [] ~?= Nothing
+                   , f [1] ~?= Just (1 NonEmpty.:| [])
+                   , f [1, 2] ~?= Just (1 NonEmpty.:| [2])
+                   ]
+            , "From (NonEmpty a) [a]"
+              ~: let f = Witch.from @(NonEmpty.NonEmpty Int) @[Int]
+                 in
+                   [ f (1 NonEmpty.:| []) ~?= [1]
+                   , f (1 NonEmpty.:| [2]) ~?= [1, 2]
+                   ]
+
+    -- Set
+            , "From [a] (Set a)"
+              ~: let f = Witch.from @[Char] @(Set.Set Char)
+                 in
+                   [ f [] ~?= Set.fromList []
+                   , f ['a'] ~?= Set.fromList ['a']
+                   , f ['a', 'b'] ~?= Set.fromList ['a', 'b']
+                   , f ['a', 'a'] ~?= Set.fromList ['a']
+                   ]
+            , "From (Set a) [a]"
+              ~: let f = Witch.from @(Set.Set Char) @[Char]
+                 in
+                   [ f (Set.fromList []) ~?= []
+                   , f (Set.fromList ['a']) ~?= ['a']
+                   , f (Set.fromList ['a', 'b']) ~?= ['a', 'b']
+                   ]
+
+    -- IntSet
+            , "From [Int] IntSet"
+              ~: let f = Witch.from @[Int] @IntSet.IntSet
+                 in
+                   [ f [] ~?= IntSet.fromList []
+                   , f [1] ~?= IntSet.fromList [1]
+                   , f [1, 2] ~?= IntSet.fromList [1, 2]
+                   ]
+            , "From IntSet [Int]"
+              ~: let f = Witch.from @IntSet.IntSet @[Int]
+                 in
+                   [ f (IntSet.fromList []) ~?= []
+                   , f (IntSet.fromList [1]) ~?= [1]
+                   , f (IntSet.fromList [1, 2]) ~?= [1, 2]
+                   ]
+
+    -- Map
+            , "From [(k, v)] (Map k v)"
+              ~: let f = Witch.from @[(Char, Int)] @(Map.Map Char Int)
+                 in
+                   [ f [] ~?= Map.empty
+                   , f [('a', 1)] ~?= Map.fromList [('a', 1)]
+                   , f [('a', 1), ('b', 2)]
+                     ~?= Map.fromList [('a', 1), ('b', 2)]
+                   , f [('a', 1), ('a', 2)] ~?= Map.fromList [('a', 2)]
+                   ]
+            , "From (Map k v) [(k, v)]"
+              ~: let f = Witch.from @(Map.Map Char Int) @[(Char, Int)]
+                 in
+                   [ f Map.empty ~?= []
+                   , f (Map.fromList [('a', 1)]) ~?= [('a', 1)]
+                   , f (Map.fromList [('a', 1), ('b', 2)])
+                     ~?= [('a', 1), ('b', 2)]
+                   ]
+
+    -- IntMap
+            , "From [(Int, v)] (IntMap v)"
+              ~: let f = Witch.from @[(Int, Char)] @(IntMap.IntMap Char)
+                 in
+                   [ f [] ~?= IntMap.fromList []
+                   , f [(1, 'a')] ~?= IntMap.fromList [(1, 'a')]
+                   , f [(1, 'a'), (2, 'b')]
+                     ~?= IntMap.fromList [(1, 'a'), (2, 'b')]
+                   , f [(1, 'a'), (1, 'b')] ~?= IntMap.fromList [(1, 'b')]
+                   ]
+            , "From (IntMap v) [(Int, v)]"
+              ~: let f = Witch.from @(IntMap.IntMap Char) @[(Int, Char)]
+                 in
+                   [ f (IntMap.fromList []) ~?= []
+                   , f (IntMap.fromList [(1, 'a')]) ~?= [(1, 'a')]
+                   , f (IntMap.fromList [(1, 'a'), (2, 'b')])
+                     ~?= [(1, 'a'), (2, 'b')]
+                   ]
+
+    -- Seq
+            , "From [a] (Seq a)"
+              ~: let f = Witch.from @[Int] @(Seq.Seq Int)
+                 in
+                   [ f [] ~?= Seq.fromList []
+                   , f [1] ~?= Seq.fromList [1]
+                   , f [1, 2] ~?= Seq.fromList [1, 2]
+                   ]
+            , "From (Seq a) [a]"
+              ~: let f = Witch.from @(Seq.Seq Int) @[Int]
+                 in
+                   [ f (Seq.fromList []) ~?= []
+                   , f (Seq.fromList [1]) ~?= [1]
+                   , f (Seq.fromList [1, 2]) ~?= [1, 2]
+                   ]
+
+    -- ByteString
+            , "From [Word8] ByteString"
+              ~: let f = Witch.from @[Word.Word8] @ByteString.ByteString
+                 in
+                   [ f [] ~?= ByteString.pack []
+                   , f [0x00] ~?= ByteString.pack [0x00]
+                   , f [0x0f, 0xf0] ~?= ByteString.pack [0x0f, 0xf0]
+                   ]
+            , "From ByteString [Word8]"
+              ~: let f = Witch.from @ByteString.ByteString @[Word.Word8]
+                 in
+                   [ f (ByteString.pack []) ~?= []
+                   , f (ByteString.pack [0x00]) ~?= [0x00]
+                   , f (ByteString.pack [0x0f, 0xf0]) ~?= [0x0f, 0xf0]
+                   ]
+            , "From ByteString LazyByteString"
+              ~: let
+                   f =
+                     Witch.from @ByteString.ByteString
+                       @LazyByteString.ByteString
+                 in
+                   [ f (ByteString.pack []) ~?= LazyByteString.pack []
+                   , f (ByteString.pack [0x00]) ~?= LazyByteString.pack [0x00]
+                   , f (ByteString.pack [0x0f, 0xf0])
+                     ~?= LazyByteString.pack [0x0f, 0xf0]
+                   ]
+            , "From ByteString ShortByteString"
+              ~: let
+                   f =
+                     Witch.from @ByteString.ByteString
+                       @ShortByteString.ShortByteString
+                 in
+                   [ f (ByteString.pack []) ~?= ShortByteString.pack []
+                   , f (ByteString.pack [0x00]) ~?= ShortByteString.pack [0x00]
+                   , f (ByteString.pack [0x0f, 0xf0])
+                     ~?= ShortByteString.pack [0x0f, 0xf0]
+                   ]
+            , "TryFrom ByteString Text"
+              ~: let f = hush . Witch.tryFrom @ByteString.ByteString @Text.Text
+                 in
+                   [ f (ByteString.pack []) ~?= Just (Text.pack "")
+                   , f (ByteString.pack [0x61]) ~?= Just (Text.pack "a")
+                   , f (ByteString.pack [0xff]) ~?= Nothing
+                   ]
+            , "TryFrom ByteString LazyText"
+              ~: let
+                   f =
+                     hush . Witch.tryFrom @ByteString.ByteString @LazyText.Text
+                 in
+                   [ f (ByteString.pack []) ~?= Just (LazyText.pack "")
+                   , f (ByteString.pack [0x61]) ~?= Just (LazyText.pack "a")
+                   , f (ByteString.pack [0xff]) ~?= Nothing
+                   ]
+            , "TryFrom ByteString String"
+              ~: let f = hush . Witch.tryFrom @ByteString.ByteString @String
+                 in
+                   [ f (ByteString.pack []) ~?= Just ""
+                   , f (ByteString.pack [0x61]) ~?= Just "a"
+                   , f (ByteString.pack [0xff]) ~?= Nothing
+                   ]
+
+    -- LazyByteString
+            , "From [Word8] LazyByteString"
+              ~: let f = Witch.from @[Word.Word8] @LazyByteString.ByteString
+                 in
+                   [ f [] ~?= LazyByteString.pack []
+                   , f [0x00] ~?= LazyByteString.pack [0x00]
+                   , f [0x0f, 0xf0] ~?= LazyByteString.pack [0x0f, 0xf0]
+                   ]
+            , "From LazyByteString [Word8]"
+              ~: let f = Witch.from @LazyByteString.ByteString @[Word.Word8]
+                 in
+                   [ f (LazyByteString.pack []) ~?= []
+                   , f (LazyByteString.pack [0x00]) ~?= [0x00]
+                   , f (LazyByteString.pack [0x0f, 0xf0]) ~?= [0x0f, 0xf0]
+                   ]
+            , "From LazyByteString ByteString"
+              ~: let
+                   f =
+                     Witch.from @LazyByteString.ByteString
+                       @ByteString.ByteString
+                 in
+                   [ f (LazyByteString.pack []) ~?= ByteString.pack []
+                   , f (LazyByteString.pack [0x00]) ~?= ByteString.pack [0x00]
+                   , f (LazyByteString.pack [0x0f, 0xf0])
+                     ~?= ByteString.pack [0x0f, 0xf0]
+                   ]
+            , "TryFrom LazyByteString LazyText"
+              ~: let
+                   f =
+                     hush
+                       . Witch.tryFrom @LazyByteString.ByteString @LazyText.Text
+                 in
+                   [ f (LazyByteString.pack []) ~?= Just (LazyText.pack "")
+                   , f (LazyByteString.pack [0x61]) ~?= Just (LazyText.pack "a")
+                   , f (LazyByteString.pack [0xff]) ~?= Nothing
+                   ]
+            , "TryFrom LazyByteString Text"
+              ~: let
+                   f =
+                     hush . Witch.tryFrom @LazyByteString.ByteString @Text.Text
+                 in
+                   [ f (LazyByteString.pack []) ~?= Just (Text.pack "")
+                   , f (LazyByteString.pack [0x61]) ~?= Just (Text.pack "a")
+                   , f (LazyByteString.pack [0xff]) ~?= Nothing
+                   ]
+            , "TryFrom LazyByteString String"
+              ~: let
+                   f = hush . Witch.tryFrom @LazyByteString.ByteString @String
+                 in
+                   [ f (LazyByteString.pack []) ~?= Just ""
+                   , f (LazyByteString.pack [0x61]) ~?= Just "a"
+                   , f (LazyByteString.pack [0xff]) ~?= Nothing
+                   ]
+
+    -- ShortByteString
+            , "From [Word8] ShortByteString"
+              ~: let
+                   f =
+                     Witch.from @[Word.Word8] @ShortByteString.ShortByteString
+                 in
+                   [ f [] ~?= ShortByteString.pack []
+                   , f [0x00] ~?= ShortByteString.pack [0x00]
+                   , f [0x0f, 0xf0] ~?= ShortByteString.pack [0x0f, 0xf0]
+                   ]
+            , "From ShortByteString [Word8]"
+              ~: let
+                   f =
+                     Witch.from @ShortByteString.ShortByteString @[Word.Word8]
+                 in
+                   [ f (ShortByteString.pack []) ~?= []
+                   , f (ShortByteString.pack [0x00]) ~?= [0x00]
+                   , f (ShortByteString.pack [0x0f, 0xf0]) ~?= [0x0f, 0xf0]
+                   ]
+            , "From ShortByteString ByteString"
+              ~: let
+                   f =
+                     Witch.from @ShortByteString.ShortByteString
+                       @ByteString.ByteString
+                 in
+                   [ f (ShortByteString.pack []) ~?= ByteString.pack []
+                   , f (ShortByteString.pack [0x00]) ~?= ByteString.pack [0x00]
+                   , f (ShortByteString.pack [0x0f, 0xf0])
+                     ~?= ByteString.pack [0x0f, 0xf0]
+                   ]
+
+    -- Text
+            , "From Text LazyText"
+              ~: let f = Witch.from @Text.Text @LazyText.Text
+                 in
+                   [ f (Text.pack "") ~?= LazyText.pack ""
+                   , f (Text.pack "a") ~?= LazyText.pack "a"
+                   , f (Text.pack "ab") ~?= LazyText.pack "ab"
+                   ]
+            , "From Text ByteString"
+              ~: let f = Witch.from @Text.Text @ByteString.ByteString
+                 in
+                   [ f (Text.pack "") ~?= ByteString.pack []
+                   , f (Text.pack "a") ~?= ByteString.pack [0x61]
+                   ]
+            , "From Text LazyByteString"
+              ~: let f = Witch.from @Text.Text @LazyByteString.ByteString
+                 in
+                   [ f (Text.pack "") ~?= LazyByteString.pack []
+                   , f (Text.pack "a") ~?= LazyByteString.pack [0x61]
+                   ]
+
+    -- LazyText
+            , "From LazyText Text"
+              ~: let f = Witch.from @LazyText.Text @Text.Text
+                 in
+                   [ f (LazyText.pack "") ~?= Text.pack ""
+                   , f (LazyText.pack "a") ~?= Text.pack "a"
+                   , f (LazyText.pack "ab") ~?= Text.pack "ab"
+                   ]
+            , "From LazyText LazyByteString"
+              ~: let f = Witch.from @LazyText.Text @LazyByteString.ByteString
+                 in
+                   [ f (LazyText.pack "") ~?= LazyByteString.pack []
+                   , f (LazyText.pack "a") ~?= LazyByteString.pack [0x61]
+                   ]
+            , "From LazyText ByteString"
+              ~: let f = Witch.from @LazyText.Text @ByteString.ByteString
+                 in
+                   [ f (LazyText.pack "") ~?= ByteString.pack []
+                   , f (LazyText.pack "a") ~?= ByteString.pack [0x61]
+                   ]
+
+    -- String
+            , "From String Text"
+              ~: let f = Witch.from @String @Text.Text
+                 in
+                   [ f "" ~?= Text.pack ""
+                   , f "a" ~?= Text.pack "a"
+                   , f "ab" ~?= Text.pack "ab"
+                   ]
+            , "From Text String"
+              ~: let f = Witch.from @Text.Text @String
+                 in
+                   [ f (Text.pack "") ~?= ""
+                   , f (Text.pack "a") ~?= "a"
+                   , f (Text.pack "ab") ~?= "ab"
+                   ]
+            , "From String LazyText"
+              ~: let f = Witch.from @String @LazyText.Text
+                 in
+                   [ f "" ~?= LazyText.pack ""
+                   , f "a" ~?= LazyText.pack "a"
+                   , f "ab" ~?= LazyText.pack "ab"
+                   ]
+            , "From LazyText String"
+              ~: let f = Witch.from @LazyText.Text @String
+                 in
+                   [ f (LazyText.pack "") ~?= ""
+                   , f (LazyText.pack "a") ~?= "a"
+                   , f (LazyText.pack "ab") ~?= "ab"
+                   ]
+            , "From String ByteString"
+              ~: let f = Witch.from @String @ByteString.ByteString
+                 in
+                   [ f "" ~?= ByteString.pack []
+                   , f "a" ~?= ByteString.pack [0x61]
+                   ]
+            , "From String LazyByteString"
+              ~: let f = Witch.from @String @LazyByteString.ByteString
+                 in
+                   [ f "" ~?= LazyByteString.pack []
+                   , f "a" ~?= LazyByteString.pack [0x61]
+                   ]
+
+    -- Day
+            , "From Integer Day"
+              ~: let f = Witch.from @Integer @Time.Day
+                 in [f 0 ~?= Time.ModifiedJulianDay 0]
+            , "From Day Integer"
+              ~: let f = Witch.from @Time.Day @Integer
+                 in [f (Time.ModifiedJulianDay 0) ~?= 0]
+
+    -- DayOfWeek
+            , "From Day DayOfWeek"
+              ~: let f = Witch.from @Time.Day @Time.DayOfWeek
+                 in [f (Time.ModifiedJulianDay 0) ~?= Time.Wednesday]
+
+    -- UniversalTime
+            , "From Rational UniversalTime"
+              ~: let f = Witch.from @Rational @Time.UniversalTime
+                 in [f 0 ~?= Time.ModJulianDate 0]
+            , "From UniversalTime Rational"
+              ~: let f = Witch.from @Time.UniversalTime @Rational
+                 in [f (Time.ModJulianDate 0) ~?= 0]
+
+    -- DiffTime
+            , "From Pico DiffTime"
+              ~: let f = Witch.from @Fixed.Pico @Time.DiffTime in [f 0 ~?= 0]
+            , "From DiffTime Pico"
+              ~: let f = Witch.from @Time.DiffTime @Fixed.Pico in [f 0 ~?= 0]
+
+    -- NominalDiffTime
+            , "From Pico NominalDiffTime"
+              ~: let f = Witch.from @Fixed.Pico @Time.NominalDiffTime
+                 in [f 0 ~?= 0]
+            , "From NominalDiffTime Pico"
+              ~: let f = Witch.from @Time.NominalDiffTime @Fixed.Pico
+                 in [f 0 ~?= 0]
+
+    -- POSIXTime
+            , "From SystemTime POSIXTime"
+              ~: let f = Witch.from @Time.SystemTime @Time.POSIXTime
+                 in [f (Time.MkSystemTime 0 0) ~?= 0]
+            , "From UTCTime POSIXTime"
+              ~: let f = Witch.from @Time.UTCTime @Time.POSIXTime
+                 in [f unixEpoch ~?= 0]
+            , "From POSIXTime UTCTime"
+              ~: let f = Witch.from @Time.POSIXTime @Time.UTCTime
+                 in [f 0 ~?= unixEpoch]
+
+    -- SystemTime
+            , "From UTCTime SystemTime"
+              ~: let f = Witch.from @Time.UTCTime @Time.SystemTime
+                 in [f unixEpoch ~?= Time.MkSystemTime 0 0]
+            , "From SystemTime AbsoluteTime"
+              ~: let f = Witch.from @Time.SystemTime @Time.AbsoluteTime
+                 in [f (Time.MkSystemTime (-3506716800) 0) ~?= Time.taiEpoch]
+            , "From SystemTime UTCTime"
+              ~: let f = Witch.from @Time.SystemTime @Time.UTCTime
+                 in [f (Time.MkSystemTime 0 0) ~?= unixEpoch]
+
+    -- TimeOfDay
+            , "From DiffTime TimeOfDay"
+              ~: let f = Witch.from @Time.DiffTime @Time.TimeOfDay
+                 in [f 0 ~?= Time.TimeOfDay 0 0 0]
+            , "From Rational TimeOfDay"
+              ~: let f = Witch.from @Rational @Time.TimeOfDay
+                 in [f 0 ~?= Time.TimeOfDay 0 0 0]
+            , "From TimeOfDay DiffTime"
+              ~: let f = Witch.from @Time.TimeOfDay @Time.DiffTime
+                 in [f (Time.TimeOfDay 0 0 0) ~?= 0]
+            , "From TimeOfDay Rational"
+              ~: let f = Witch.from @Time.TimeOfDay @Rational
+                 in [f (Time.TimeOfDay 0 0 0) ~?= 0]
+
+    -- CalendarDiffTime
+            , "From CalendarDiffDays CalendarDiffTime"
+              ~: let
+                   f = Witch.from @Time.CalendarDiffDays @Time.CalendarDiffTime
+                 in
+                   [f (Time.CalendarDiffDays 0 0) ~?= Time.CalendarDiffTime 0 0]
+            , "From NominalDiffTime CalendarDiffTime"
+              ~: let
+                   f = Witch.from @Time.NominalDiffTime @Time.CalendarDiffTime
+                 in [f 0 ~?= Time.CalendarDiffTime 0 0]
+
+    -- ZonedTime
+            , "From ZonedTime UTCTime"
+              ~: let f = Witch.from @Time.ZonedTime @Time.UTCTime
+                 in
+                   [ f
+                         (Time.ZonedTime
+                           (Time.LocalTime
+                             (Time.ModifiedJulianDay 0)
+                             (Time.TimeOfDay 0 0 0)
+                           )
+                           Time.utc
+                         )
+                       ~?= Time.UTCTime (Time.ModifiedJulianDay 0) 0
+                   ]
+            ]
+       ]
 
 unixEpoch :: Time.UTCTime
 unixEpoch = Time.UTCTime (Time.ModifiedJulianDay 40587) 0
diff --git a/witch.cabal b/witch.cabal
--- a/witch.cabal
+++ b/witch.cabal
@@ -1,7 +1,7 @@
 cabal-version: 2.2
 
 name: witch
-version: 0.3.4.1
+version: 0.3.4.2
 synopsis: Convert values from one type into another.
 description: Witch converts values from one type into another.
 
@@ -16,6 +16,11 @@
   location: https://github.com/tfausak/witch
   type: git
 
+flag pedantic
+  default: False
+  description: Enables @-Werror@, which turns warnings into errors.
+  manual: True
+
 common basics
   build-depends:
     , base >= 4.10.0 && < 4.17
@@ -46,10 +51,14 @@
     ghc-options:
       -Wno-missing-safe-haskell-mode
       -Wno-prepositive-qualified-module
-      
+
   if impl(ghc >= 9.2)
     ghc-options:
       -Wno-missing-kind-signatures
+
+  if flag(pedantic)
+    ghc-options:
+      -Werror
 
 library
   import: basics