Safe Haskell	None
Language	Haskell2010

Witch.From

Synopsis

class From source target where
- from :: source -> target

Documentation

class From source target where Source #

This type class is for converting values from some source type into some other target type. The constraint From source target means that you can convert from a value of type source into a value of type target.

This type class is for conversions that always succeed. If your conversion sometimes fails, consider implementing TryFrom instead.

Minimal complete definition

Nothing

Methods

from :: source -> target Source #

This method implements the conversion of a value between types. At call sites you may prefer to use into instead.

-- Avoid this:
from (x :: s)

-- Prefer this:
from @s x

The default implementation of this method simply calls coerce, which works for types that have the same runtime representation. This means that for newtypes you do not need to implement this method at all. For example:

>>> newtype Name = Name String
>>> instance From Name String
>>> instance From String Name

default from :: Coercible source target => source -> target Source #

Instances

Instances details

From Double Float Source #	Uses `double2Float`. This necessarily loses some precision.
Instance details Defined in Witch.Instances Methods from :: Double -> Float Source #
From Float Double Source #	Uses `float2Double`.
Instance details Defined in Witch.Instances Methods from :: Float -> Double Source #
From Int Int64 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int -> Int64 Source #
From Int Integer Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int -> Integer Source #
From Int8 Double Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int8 -> Double Source #
From Int8 Float Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int8 -> Float Source #
From Int8 Int Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int8 -> Int Source #
From Int8 Int16 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int8 -> Int16 Source #
From Int8 Int32 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int8 -> Int32 Source #
From Int8 Int64 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int8 -> Int64 Source #
From Int8 Integer Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int8 -> Integer Source #
From Int16 Double Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int16 -> Double Source #
From Int16 Float Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int16 -> Float Source #
From Int16 Int Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int16 -> Int Source #
From Int16 Int32 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int16 -> Int32 Source #
From Int16 Int64 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int16 -> Int64 Source #
From Int16 Integer Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int16 -> Integer Source #
From Int32 Double Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int32 -> Double Source #
From Int32 Int64 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int32 -> Int64 Source #
From Int32 Integer Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int32 -> Integer Source #
From Int64 Integer Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Int64 -> Integer Source #
From Integer Day Source #	Uses `ModifiedJulianDay`.
Instance details Defined in Witch.Instances Methods from :: Integer -> Day Source #
From Natural Integer Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Natural -> Integer Source #
From Rational Double Source #	Uses `fromRational`. This necessarily loses some precision.
Instance details Defined in Witch.Instances Methods from :: Rational -> Double Source #
From Rational Float Source #	Uses `fromRational`. This necessarily loses some precision.
Instance details Defined in Witch.Instances Methods from :: Rational -> Float Source #
From Rational TimeOfDay Source #	Uses `dayFractionToTimeOfDay`.
Instance details Defined in Witch.Instances Methods from :: Rational -> TimeOfDay Source #
From Rational UniversalTime Source #	Uses `ModJulianDate`.
Instance details Defined in Witch.Instances Methods from :: Rational -> UniversalTime Source #
From Word Integer Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word -> Integer Source #
From Word Natural Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word -> Natural Source #
From Word Word64 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word -> Word64 Source #
From Word8 Double Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word8 -> Double Source #
From Word8 Float Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word8 -> Float Source #
From Word8 Int Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word8 -> Int Source #
From Word8 Int16 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word8 -> Int16 Source #
From Word8 Int32 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word8 -> Int32 Source #
From Word8 Int64 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word8 -> Int64 Source #
From Word8 Integer Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word8 -> Integer Source #
From Word8 Natural Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word8 -> Natural Source #
From Word8 Word Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word8 -> Word Source #
From Word8 Word16 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word8 -> Word16 Source #
From Word8 Word32 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word8 -> Word32 Source #
From Word8 Word64 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word8 -> Word64 Source #
From Word16 Double Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word16 -> Double Source #
From Word16 Float Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word16 -> Float Source #
From Word16 Int Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word16 -> Int Source #
From Word16 Int32 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word16 -> Int32 Source #
From Word16 Int64 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word16 -> Int64 Source #
From Word16 Integer Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word16 -> Integer Source #
From Word16 Natural Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word16 -> Natural Source #
From Word16 Word Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word16 -> Word Source #
From Word16 Word32 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word16 -> Word32 Source #
From Word16 Word64 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word16 -> Word64 Source #
From Word32 Double Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word32 -> Double Source #
From Word32 Int64 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word32 -> Int64 Source #
From Word32 Integer Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word32 -> Integer Source #
From Word32 Natural Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word32 -> Natural Source #
From Word32 Word64 Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word32 -> Word64 Source #
From Word64 Integer Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word64 -> Integer Source #
From Word64 Natural Source #	Uses `fromIntegral`.
Instance details Defined in Witch.Instances Methods from :: Word64 -> Natural Source #
From a a Source #	Uses `id`.
Instance details Defined in Witch.Instances Methods from :: a -> a Source #
From Pico NominalDiffTime Source #	Uses `secondsToNominalDiffTime`.
Instance details Defined in Witch.Instances Methods from :: Pico -> NominalDiffTime Source #
From Pico DiffTime Source #	Uses `realToFrac`.
Instance details Defined in Witch.Instances Methods from :: Pico -> DiffTime Source #
From String ByteString Source #	Converts via `Text`.
Instance details Defined in Witch.Instances Methods from :: String -> ByteString Source #
From String ByteString Source #	Converts via `Text`.
Instance details Defined in Witch.Instances Methods from :: String -> ByteString Source #
From String Text Source #	Uses `pack`. Some `Char` values cannot be represented in `Text` and will be replaced with `'\xFFFD'`.
Instance details Defined in Witch.Instances Methods from :: String -> Text Source #
From String Text Source #	Uses `pack`. Some `Char` values cannot be represented in `Text` and will be replaced with `'\xFFFD'`.
Instance details Defined in Witch.Instances Methods from :: String -> Text Source #
From ShortByteString ByteString Source #	Uses `fromShort`.
Instance details Defined in Witch.Instances Methods from :: ShortByteString -> ByteString Source #
From ByteString ByteString Source #	Uses `toStrict`.
Instance details Defined in Witch.Instances Methods from :: ByteString0 -> ByteString Source #
From ByteString ShortByteString Source #	Uses `toShort`.
Instance details Defined in Witch.Instances Methods from :: ByteString -> ShortByteString Source #
From ByteString ByteString Source #	Uses `fromStrict`.
Instance details Defined in Witch.Instances Methods from :: ByteString -> ByteString0 Source #
From Text String Source #	Uses `unpack`.
Instance details Defined in Witch.Instances Methods from :: Text -> String Source #
From Text ByteString Source #	Uses `encodeUtf8`.
Instance details Defined in Witch.Instances Methods from :: Text -> ByteString Source #
From Text ByteString Source #	Converts via `ByteString`.
Instance details Defined in Witch.Instances Methods from :: Text -> ByteString Source #
From Text Text Source #	Uses `toStrict`.
Instance details Defined in Witch.Instances Methods from :: Text0 -> Text Source #
From Text String Source #	Uses `unpack`.
Instance details Defined in Witch.Instances Methods from :: Text -> String Source #
From Text ByteString Source #	Converts via `ByteString`.
Instance details Defined in Witch.Instances Methods from :: Text -> ByteString Source #
From Text ByteString Source #	Uses `encodeUtf8`.
Instance details Defined in Witch.Instances Methods from :: Text -> ByteString Source #
From Text Text Source #	Uses `fromStrict`.
Instance details Defined in Witch.Instances Methods from :: Text -> Text0 Source #
From ZonedTime UTCTime Source #	Uses `zonedTimeToUTC`.
Instance details Defined in Witch.Instances Methods from :: ZonedTime -> UTCTime Source #
From TimeOfDay Rational Source #	Uses `timeOfDayToDayFraction`.
Instance details Defined in Witch.Instances Methods from :: TimeOfDay -> Rational Source #
From TimeOfDay DiffTime Source #	Uses `timeOfDayToTime`.
Instance details Defined in Witch.Instances Methods from :: TimeOfDay -> DiffTime Source #
From UniversalTime Rational Source #	Uses `getModJulianDate`.
Instance details Defined in Witch.Instances Methods from :: UniversalTime -> Rational Source #
From UTCTime SystemTime Source #	Uses `utcToSystemTime`.
Instance details Defined in Witch.Instances Methods from :: UTCTime -> SystemTime Source #
From UTCTime POSIXTime Source #	Uses `utcTimeToPOSIXSeconds`.
Instance details Defined in Witch.Instances Methods from :: UTCTime -> POSIXTime Source #
From SystemTime UTCTime Source #	Uses `systemToUTCTime`.
Instance details Defined in Witch.Instances Methods from :: SystemTime -> UTCTime Source #
From SystemTime POSIXTime Source #	Uses `systemToPOSIXTime`.
Instance details Defined in Witch.Instances Methods from :: SystemTime -> POSIXTime Source #
From SystemTime AbsoluteTime Source #	Uses `systemToTAITime`.
Instance details Defined in Witch.Instances Methods from :: SystemTime -> AbsoluteTime Source #
From POSIXTime UTCTime Source #	Uses `posixSecondsToUTCTime`.
Instance details Defined in Witch.Instances Methods from :: POSIXTime -> UTCTime Source #
From NominalDiffTime Pico Source #	Uses `nominalDiffTimeToSeconds`.
Instance details Defined in Witch.Instances Methods from :: NominalDiffTime -> Pico Source #
From NominalDiffTime CalendarDiffTime Source #	Uses `calendarTimeTime`.
Instance details Defined in Witch.Instances Methods from :: NominalDiffTime -> CalendarDiffTime Source #
From DiffTime Pico Source #	Uses `realToFrac`.
Instance details Defined in Witch.Instances Methods from :: DiffTime -> Pico Source #
From DiffTime TimeOfDay Source #	Uses `timeToTimeOfDay`.
Instance details Defined in Witch.Instances Methods from :: DiffTime -> TimeOfDay Source #
From Day Integer Source #	Uses `toModifiedJulianDay`.
Instance details Defined in Witch.Instances Methods from :: Day -> Integer Source #
From Day DayOfWeek Source #	Uses `dayOfWeek`.
Instance details Defined in Witch.Instances Methods from :: Day -> DayOfWeek Source #
From CalendarDiffDays CalendarDiffTime Source #	Uses `calendarTimeDays`.
Instance details Defined in Witch.Instances Methods from :: CalendarDiffDays -> CalendarDiffTime Source #
Num a => From a (Complex a) Source #	Uses `(:+)` with an imaginary part of 0.
Instance details Defined in Witch.Instances Methods from :: a -> Complex a Source #
Integral a => From a (Ratio a) Source #	Uses `(%)` with a denominator of 1.
Instance details Defined in Witch.Instances Methods from :: a -> Ratio a Source #
From ShortByteString [Word8] Source #	Uses `unpack`.
Instance details Defined in Witch.Instances Methods from :: ShortByteString -> [Word8] Source #
From ByteString [Word8] Source #	Uses `unpack`.
Instance details Defined in Witch.Instances Methods from :: ByteString -> [Word8] Source #
From ByteString [Word8] Source #	Uses `unpack`.
Instance details Defined in Witch.Instances Methods from :: ByteString -> [Word8] Source #
From IntSet [Int] Source #	Uses `toAscList`.
Instance details Defined in Witch.Instances Methods from :: IntSet -> [Int] Source #
From Integer (Fixed a) Source #	Uses `MkFixed`. This means `from @Integer @Centi 2` is `0.02` rather than `2.00`.
Instance details Defined in Witch.Instances Methods from :: Integer -> Fixed a Source #
From [Int] IntSet Source #	Uses `fromList`.
Instance details Defined in Witch.Instances Methods from :: [Int] -> IntSet Source #
From [Word8] ShortByteString Source #	Uses `pack`.
Instance details Defined in Witch.Instances Methods from :: [Word8] -> ShortByteString Source #
From [Word8] ByteString Source #	Uses `pack`.
Instance details Defined in Witch.Instances Methods from :: [Word8] -> ByteString Source #
From [Word8] ByteString Source #	Uses `pack`.
Instance details Defined in Witch.Instances Methods from :: [Word8] -> ByteString Source #
From [(Int, v)] (IntMap v) Source #	Uses `fromList`. If there are duplicate keys, later values will overwrite earlier ones.
Instance details Defined in Witch.Instances Methods from :: [(Int, v)] -> IntMap v Source #
From [a] (Seq a) Source #	Uses `fromList`.
Instance details Defined in Witch.Instances Methods from :: [a] -> Seq a Source #
Ord a => From [a] (Set a) Source #	Uses `fromList`.
Instance details Defined in Witch.Instances Methods from :: [a] -> Set a Source #
From (NonEmpty a) [a] Source #	Uses `toList`.
Instance details Defined in Witch.Instances Methods from :: NonEmpty a -> [a] Source #
From (IntMap v) [(Int, v)] Source #	Uses `toAscList`.
Instance details Defined in Witch.Instances Methods from :: IntMap v -> [(Int, v)] Source #
From (Seq a) [a] Source #	Uses `toList`.
Instance details Defined in Witch.Instances Methods from :: Seq a -> [a] Source #
From (Set a) [a] Source #	Uses `toAscList`.
Instance details Defined in Witch.Instances Methods from :: Set a -> [a] Source #
Ord k => From [(k, v)] (Map k v) Source #	Uses `fromList`. If there are duplicate keys, later values will overwrite earlier ones.
Instance details Defined in Witch.Instances Methods from :: [(k, v)] -> Map k v Source #
HasResolution a => From (Fixed a) Rational Source #	Uses `toRational`.
Instance details Defined in Witch.Instances Methods from :: Fixed a -> Rational Source #
From (Fixed a) Integer Source #	Uses `MkFixed`. This means `from @Centi @Integer 3.00` is `300` rather than `3`.
Instance details Defined in Witch.Instances Methods from :: Fixed a -> Integer Source #
From (Map k v) [(k, v)] Source #	Uses `toAscList`.
Instance details Defined in Witch.Instances Methods from :: Map k v -> [(k, v)] Source #
From (TryFromException source oldTarget) (TryFromException source newTarget) Source #	Uses `coerce`.
Instance details Defined in Witch.Instances Methods from :: TryFromException source oldTarget -> TryFromException source newTarget Source #

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