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1. adjustWithKey :: Ord k => (k -> a -> a) -> k -> Map k a -> Map k a

   rio	RIO.Map

   Adjust a value at a specific key. When the key is not a member of the map, the original map is returned.

   let f key x = (show key) ++ ":new " ++ x
   adjustWithKey f 5 (fromList [(5,"a"), (3,"b")]) == fromList [(3, "b"), (5, "5:new a")]
   adjustWithKey f 7 (fromList [(5,"a"), (3,"b")]) == fromList [(3, "b"), (5, "a")]
   adjustWithKey f 7 empty                         == empty
   

2. fromJust :: HasCallStack => Maybe a -> a

   rio	RIO.Partial

   The fromJust function extracts the element out of a Just and throws an error if its argument is Nothing.

   Examples

   Basic usage:

   >>> fromJust (Just 1)
   1
   

   >>> 2 * (fromJust (Just 10))
   20
   

   >>> 2 * (fromJust Nothing)
   *** Exception: Maybe.fromJust: Nothing
   ...
   

   WARNING: This function is partial. You can use case-matching instead.

3. isJust :: Maybe a -> Bool

   rio	RIO.Prelude

   The isJust function returns True iff its argument is of the form Just _.

   Examples

   Basic usage:

   >>> isJust (Just 3)
   True
   

   >>> isJust (Just ())
   True
   

   >>> isJust Nothing
   False
   

   Only the outer constructor is taken into consideration:

   >>> isJust (Just Nothing)
   True
   

4. adjust :: (a -> a) -> Int -> Seq a -> Seq a

   rio	RIO.Seq

   Update the element at the specified position. If the position is out of range, the original sequence is returned. adjust can lead to poor performance and even memory leaks, because it does not force the new value before installing it in the sequence. adjust' should usually be preferred.

5. adjust' :: (a -> a) -> Int -> Seq a -> Seq a

   rio	RIO.Seq

   Update the element at the specified position. If the position is out of range, the original sequence is returned. The new value is forced before it is installed in the sequence.

   adjust' f i xs =
   case xs !? i of
   Nothing -> xs
   Just x -> let !x' = f x
   in update i x' xs
   

6. findJustDef :: a -> (a -> Bool) -> [a] -> a

   errors	Control.Error

   No documentation available.

7. fromJustDef :: a -> Maybe a -> a

   errors	Control.Error

   An alternative name for fromMaybe, to fit the naming scheme of this package. Generally using fromMaybe directly would be considered better style.

8. isJust :: Maybe a -> Bool

   errors	Control.Error

   The isJust function returns True iff its argument is of the form Just _.

   Examples

   Basic usage:

   >>> isJust (Just 3)
   True
   

   >>> isJust (Just ())
   True
   

   >>> isJust Nothing
   False
   

   Only the outer constructor is taken into consideration:

   >>> isJust (Just Nothing)
   True
   

9. lookupJustDef :: Eq a => b -> a -> [(a, b)] -> b

   errors	Control.Error

   No documentation available.

10. tryJust :: forall (m :: Type -> Type) e a . Monad m => e -> Maybe a -> ExceptT e m a

    errors	Control.Error.Safe

    A fromJust that fails in the ExceptT monad

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