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1. takeWhileJust :: [Maybe a] -> [a]

   utility-ht	Data.List.HT

   This is the cousin of takeWhile analogously to catMaybes being the cousin of filter.

   >>> takeWhileJust [Just 'a', Just 'b', Nothing, Just 'c']
   "ab"
   

   Example: Keep the heads of sublists until an empty list occurs.

   >>> takeWhileJust $ map (fmap fst . viewL) ["abc","def","","xyz"]
   "ad"
   

   For consistency with takeWhile, partitionMaybe and dropWhileNothing it should have been:

   takeWhileJust_ :: (a -> Maybe b) -> a -> [b]
   

   However, both variants are interchangeable:

   takeWhileJust_ f == takeWhileJust . map f
   takeWhileJust == takeWhileJust_ id
   

2. catchJust :: (HasCallStack, MonadCatch m, Exception e) => (e -> Maybe b) -> m a -> (b -> m a) -> m a

   safe-exceptions	Control.Exception.Safe

   catchJust is like catch but it takes an extra argument which is an exception predicate, a function which selects which type of exceptions we're interested in.

3. handleJust :: (HasCallStack, MonadCatch m, Exception e) => (e -> Maybe b) -> (b -> m a) -> m a -> m a

   safe-exceptions	Control.Exception.Safe

   Flipped catchJust.

4. tryJust :: (HasCallStack, MonadCatch m, Exception e) => (e -> Maybe b) -> m a -> m (Either b a)

   safe-exceptions	Control.Exception.Safe

   A variant of try that takes an exception predicate to select which exceptions are caught.

5. untilJust :: Monad m => m (Maybe a) -> IterT m a

   free	Control.Monad.Trans.Iter

   Repeatedly run a computation until it produces a Just value. This can be useful when paired with a monad that has side effects. For example, we may have genId :: IO (Maybe Id) that uses a random number generator to allocate ids, but fails if it finds a collision. We can repeatedly run this with

   retract (untilJust genId) :: IO Id
   

6. promotedJustDataCon :: TyCon

   ghc	GHC.Builtin.Types

   No documentation available.

7. mapAdjust :: (v -> v) -> Label -> LabelMap v -> LabelMap v

   ghc	GHC.Cmm.Dataflow.Label

   No documentation available.

8. adjustEdgeWeight :: CFG -> (EdgeWeight -> EdgeWeight) -> BlockId -> BlockId -> CFG

   ghc	GHC.CmmToAsm.CFG

   Adjust the weight between the blocks using the given function. If there is no such edge returns the original map.

9. mkJustExpr :: Type -> CoreExpr -> CoreExpr

   ghc	GHC.Core.Make

   Makes a Just from a value of the specified type

10. adjustDTyConEnv :: (a -> a) -> DTyConEnv a -> TyCon -> DTyConEnv a

    ghc	GHC.Core.TyCon.Env

    No documentation available.

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