Implement pure-Haskell asciiPrefixLength

haskell · Jan 28, 2024 · b070bac · b070bac
1 parent 97ae28a
commit b070bac
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/Data/Text/Internal/IsAscii.hs b/src/Data/Text/Internal/IsAscii.hs
@@ -77,7 +77,7 @@ isAscii (Text (A.ByteArray arr) off len) =
 -- | Length of the longest ASCII prefix.
 asciiPrefixLength :: ByteString -> Int
 #if defined(PURE_HASKELL)
-asciiPrefixLength = P.const 0
+asciiPrefixLength = BS.length P.. BS.takeWhile (P.< 0x80)
 #else
 asciiPrefixLength bs = unsafeDupablePerformIO $ withBS bs $ \ fp len ->
   unsafeWithForeignPtr fp $ \src -> do