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Merged
Bodigrim merged 1 commit into from
Sep 18, 2026
Merged

Add fromString = pack to work with upcoming QualifiedStrings #709

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9 changes: 7 additions & 2 deletions src/Data/Text.hs
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Original file line number Diff line number Diff line change
Expand Up @@ -59,6 +59,7 @@ module Data.Text

-- * Creation and elimination
, pack
, fromString
, unpack
, singleton
, empty
Expand Down Expand Up @@ -248,7 +249,7 @@ import Data.Coerce (coerce)
import Data.Functor.Identity (Identity(..))
import Data.Monoid (Monoid(..))
import Data.Semigroup (Semigroup(..))
import Data.String (IsString(..))
import qualified Data.String
import Data.Text.Internal.ArrayUtils (memchr)
import Data.Text.Internal.IsAscii (isAscii)
import Data.Text.Internal.Reverse (reverse)
Expand Down Expand Up @@ -403,7 +404,7 @@ instance Monoid Text where
-- >>> :set -XOverloadedStrings
-- >>> "\55555" :: Text
-- "\65533"
instance IsString Text where
instance Data.String.IsString Text where
fromString = pack

-- | Performs replacement on invalid scalar values:
Expand Down Expand Up @@ -2301,6 +2302,10 @@ cSsizeToInt = P.fromIntegral
word8ToInt8 :: Word8 -> Int8
word8ToInt8 = P.fromIntegral

-- | Synonym of 'pack' for the sake of @{-# LANGUAGE QualifiedStrings #-}@.
fromString :: String -> Text
fromString = pack

-------------------------------------------------
-- NOTE: the named chunk below used by doctest;
-- verify the doctests via `doctest -fobject-code Data/Text.hs`
Expand Down
9 changes: 7 additions & 2 deletions src/Data/Text/Lazy.hs
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Expand Up @@ -52,6 +52,7 @@ module Data.Text.Lazy

-- * Creation and elimination
, pack
, fromString
, unpack
, singleton
, empty
Expand Down Expand Up @@ -235,7 +236,7 @@ import Data.List.NonEmpty (NonEmpty(..))
import qualified Data.List.NonEmpty as NE
import Data.Monoid (Monoid(..))
import Data.Semigroup (Semigroup(..))
import Data.String (IsString(..))
import qualified Data.String
import qualified Data.Text as T
import qualified Data.Text.Array as A
import qualified Data.Text.Internal as T
Expand Down Expand Up @@ -351,7 +352,7 @@ instance Monoid Text where
-- >>> :set -XOverloadedStrings
-- >>> "\55555" :: Data.Text.Lazy.Text
-- "\65533"
instance IsString Text where
instance Data.String.IsString Text where
fromString = pack

-- | Performs replacement on invalid scalar values:
Expand Down Expand Up @@ -1939,3 +1940,7 @@ intToInt64 = fromIntegral

int64ToInt :: Int64 -> Exts.Int
int64ToInt = fromIntegral

-- | Synonym of 'pack' for the sake of @{-# LANGUAGE QualifiedStrings #-}@.
fromString :: String -> Text
fromString = pack
51 changes: 26 additions & 25 deletions tests/Tests/ShareEmpty.hs
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Expand Up @@ -6,13 +6,14 @@

{-# OPTIONS_GHC -Wno-unrecognised-warning-flags #-}
{-# OPTIONS_GHC -Wno-x-partial #-}
{- HLINT ignore "Avoid restricted function" -}

module Tests.ShareEmpty
( tests
) where

import Control.Exception (evaluate)
import Data.Text
import Data.Text (Text)
#if __GLASGOW_HASKELL__ >= 914
import Language.Haskell.TH.Lift (lift)
#else
Expand All @@ -30,9 +31,9 @@ import qualified Data.Text as T
-- | assert that a text value is represented by the same pointer
-- as the 'empty' value.
assertPtrEqEmpty :: HasCallStack => Text -> IO ()
assertPtrEqEmpty t = do
assertPtrEqEmpty t = do
t' <- evaluate t
empty' <- evaluate empty
empty' <- evaluate T.empty
assertEqual "" empty' t'
case reallyUnsafePtrEquality# empty' t' of
1# -> pure ()
Expand All @@ -44,32 +45,32 @@ tests = testGroup "empty Text values are shared"
[ testCase "empty = empty" $ assertPtrEqEmpty T.empty
, testCase "pack \"\" = empty" $ assertPtrEqEmpty $ T.pack ""
, testCase "fromString \"\" = empty" $ assertPtrEqEmpty $ fromString ""
, testCase "$(lift \"\") = empty" $ assertPtrEqEmpty $ $(lift (pack ""))
, testCase "$(lift \"\") = empty" $ assertPtrEqEmpty $ $(lift (T.pack ""))
, testCase "tail of a singleton = empty" $ assertPtrEqEmpty $ T.tail "a"
, testCase "init of a singleton = empty" $ assertPtrEqEmpty $ T.init "b"
, testCase "map _ empty = empty" $ assertPtrEqEmpty $ T.map id empty
, testCase "map _ empty = empty" $ assertPtrEqEmpty $ T.map id T.empty
, testCase "intercalate _ [] = empty" $ assertPtrEqEmpty $ T.intercalate ", " []
, testCase "intersperse _ empty = empty" $ assertPtrEqEmpty $ T.intersperse ',' ""
, testCase "reverse empty = empty" $ assertPtrEqEmpty $
T.reverse empty
T.reverse T.empty
, testCase "replace _ _ empty = empty" $ assertPtrEqEmpty $
T.replace "needle" "replacement" empty
T.replace "needle" "replacement" T.empty
, testCase "toCaseFold empty = empty" $ assertPtrEqEmpty $ T.toCaseFold ""
, testCase "toLower empty = empty" $ assertPtrEqEmpty $ T.toLower ""
, testCase "toUpper empty = empty" $ assertPtrEqEmpty $ T.toUpper ""
, testCase "toTitle empty = empty" $ assertPtrEqEmpty $ T.toTitle ""
, testCase "justifyLeft 0 _ empty = empty" $ assertPtrEqEmpty $
justifyLeft 0 ' ' empty
T.justifyLeft 0 ' ' T.empty
, testCase "justifyRight 0 _ empty = empty" $ assertPtrEqEmpty $
justifyRight 0 ' ' empty
T.justifyRight 0 ' ' T.empty
, testCase "center 0 _ empty = empty" $ assertPtrEqEmpty $
T.center 0 ' ' empty
T.center 0 ' ' T.empty
, testCase "transpose [empty] = [empty]" $ mapM_ assertPtrEqEmpty $
T.transpose [empty]
T.transpose [T.empty]
, testCase "concat [] = empty" $ assertPtrEqEmpty $ T.concat []
, testCase "concat [empty] = empty" $ assertPtrEqEmpty $ T.concat [empty]
, testCase "concat [empty] = empty" $ assertPtrEqEmpty $ T.concat [T.empty]
, testCase "replicate 0 _ = empty" $ assertPtrEqEmpty $ T.replicate 0 "x"
, testCase "replicate _ empty = empty" $ assertPtrEqEmpty $ T.replicate 10 empty
, testCase "replicate _ empty = empty" $ assertPtrEqEmpty $ T.replicate 10 T.empty
, testCase "unfoldr (const Nothing) _ = empty" $ assertPtrEqEmpty $
T.unfoldr (const Nothing) ()
, testCase "take 0 _ = empty" $ assertPtrEqEmpty $
Expand All @@ -87,12 +88,12 @@ tests = testGroup "empty Text values are shared"
, testCase "dropWhile (const True) x = empty" $ assertPtrEqEmpty $
T.dropWhile (const True) "xyz"
, testCase "dropWhileEnd (const True) x = empty" $ assertPtrEqEmpty $
dropWhileEnd (const True) "xyz"
T.dropWhileEnd (const True) "xyz"
, testCase "dropAround _ empty = empty" $ assertPtrEqEmpty $
dropAround (const True) empty
, testCase "stripStart empty = empty" $ assertPtrEqEmpty $ T.stripStart empty
, testCase "stripEnd empty = empty" $ assertPtrEqEmpty $ T.stripEnd empty
, testCase "strip empty = empty" $ assertPtrEqEmpty $ T.strip empty
T.dropAround (const True) T.empty
, testCase "stripStart empty = empty" $ assertPtrEqEmpty $ T.stripStart T.empty
, testCase "stripEnd empty = empty" $ assertPtrEqEmpty $ T.stripEnd T.empty
, testCase "strip empty = empty" $ assertPtrEqEmpty $ T.strip T.empty
, testCase "fst (splitAt 0 _) = empty" $ assertPtrEqEmpty $ fst $ T.splitAt 0 "123"
, testCase "snd (splitAt n x) = empty where n > len x" $ assertPtrEqEmpty $
snd $ T.splitAt 5 "123"
Expand All @@ -112,13 +113,13 @@ tests = testGroup "empty Text values are shared"
assertPtrEqEmpty . fst =<< T.spanEndM (const $ pure True) "123"
, testCase "snd (spanEndM (const $ pure False) _) = empty" $
assertPtrEqEmpty . snd =<< T.spanEndM (const $ pure False) "123"
, testCase "groupBy _ empty = [empty]" $ mapM_ assertPtrEqEmpty $ T.groupBy (==) empty
, testCase "inits empty = [empty]" $ mapM_ assertPtrEqEmpty $ T.inits empty
, testCase "initsNE empty = singleton empty" $ mapM_ assertPtrEqEmpty $ T.initsNE empty
, testCase "groupBy _ empty = [empty]" $ mapM_ assertPtrEqEmpty $ T.groupBy (==) T.empty
, testCase "inits empty = [empty]" $ mapM_ assertPtrEqEmpty $ T.inits T.empty
, testCase "initsNE empty = singleton empty" $ mapM_ assertPtrEqEmpty $ T.initsNE T.empty
, testCase "inits _ = [empty, ...]" $ assertPtrEqEmpty $ L.head $ T.inits "123"
, testCase "initsNE _ = empty :| ..." $ assertPtrEqEmpty $ NonEmptyList.head $ T.initsNE "123"
, testCase "tails empty = [empty]" $ mapM_ assertPtrEqEmpty $ T.tails empty
, testCase "tailsNE empty = singleton empty" $ mapM_ assertPtrEqEmpty $ T.tailsNE empty
, testCase "tails empty = [empty]" $ mapM_ assertPtrEqEmpty $ T.tails T.empty
, testCase "tailsNE empty = singleton empty" $ mapM_ assertPtrEqEmpty $ T.tailsNE T.empty
, testCase "tails _ = [..., empty]" $ assertPtrEqEmpty $ L.last $ T.tails "123"
, testCase "tailsNE _ = reverse (empty :| ...)" $ assertPtrEqEmpty $ NonEmptyList.last $ T.tailsNE "123"
, testCase "split _ empty = [empty]" $ mapM_ assertPtrEqEmpty $ T.split (== 'a') ""
Expand All @@ -127,9 +128,9 @@ tests = testGroup "empty Text values are shared"
, testCase "unlines [] = empty" $ assertPtrEqEmpty $ T.unlines []
, testCase "unwords [] = empty" $ assertPtrEqEmpty $ T.unwords []
, testCase "stripPrefix empty empty = Just empty" $ mapM_ assertPtrEqEmpty $
T.stripPrefix empty empty
T.stripPrefix T.empty T.empty
, testCase "stripSuffix empty empty = Just empty" $ mapM_ assertPtrEqEmpty $
T.stripSuffix empty empty
T.stripSuffix T.empty T.empty
, testCase "commonPrefixes \"xyz\" \"123\" = Just (_, empty, _)" $
mapM_ (assertPtrEqEmpty . (\(_, x, _) -> x)) $ T.commonPrefixes "xyz" "123"
, testCase "commonPrefixes \"xyz\" \"xyz\" = Just (_, _, empty)" $
Expand Down
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