diff options
| -rwxr-xr-x | libraries/base/GHC/Exts.hs | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/libraries/base/GHC/Exts.hs b/libraries/base/GHC/Exts.hs index 47392ada3d..45f6705b0c 100755 --- a/libraries/base/GHC/Exts.hs +++ b/libraries/base/GHC/Exts.hs @@ -113,6 +113,8 @@ import Data.Ord import Data.Version ( Version(..), makeVersion ) import qualified Debug.Trace +import Control.Applicative (ZipList(..)) + -- XXX This should really be in Data.Tuple, where the definitions are maxTupleSize :: Int maxTupleSize = 62 @@ -209,6 +211,12 @@ instance IsList [a] where fromList = id toList = id +-- | @since +instance IsList (ZipList a) where + type (Item (ZipList a)) = a + fromList = ZipList + toList (ZipList as) = as + -- | @since 4.9.0.0 instance IsList (NonEmpty a) where type Item (NonEmpty a) = a @@ -261,7 +269,7 @@ atomicModifyMutVar# mv f s = -- 'SmallMutableArray#' is either the original 'SmallMutableArray#' -- resized in-place or, if not possible, a newly allocated -- 'SmallMutableArray#' with the original content copied over. --- +-- -- To avoid undefined behaviour, the original 'SmallMutableArray#' shall -- not be accessed anymore after a 'resizeSmallMutableArray#' has been -- performed. Moreover, no reference to the old one should be kept in order |