Safe Haskell | Safe |
---|---|
Language | Haskell2010 |
Synopsis
- (!) :: Ord k => Map k a -> k -> a
- elemAt :: Int -> Map k a -> (k, a)
- deleteAt :: Int -> Map k a -> Map k a
- findIndex :: Ord k => k -> Map k a -> Int
- updateAt :: (k -> a -> Maybe a) -> Int -> Map k a -> Map k a
- findMin :: Map k a -> (k, a)
- findMax :: Map k a -> (k, a)
- deleteFindMin :: Map k a -> ((k, a), Map k a)
- deleteFindMax :: Map k a -> ((k, a), Map k a)
Operators
(!) :: Ord k => Map k a -> k -> a infixl 9 #
O(log n). Find the value at a key.
Calls error
when the element can not be found.
fromList [(5,'a'), (3,'b')] ! 1 Error: element not in the map fromList [(5,'a'), (3,'b')] ! 5 == 'a'
Indexed
elemAt :: Int -> Map k a -> (k, a) #
O(log n). Retrieve an element by its index, i.e. by its zero-based
index in the sequence sorted by keys. If the index is out of range (less
than zero, greater or equal to size
of the map), error
is called.
elemAt 0 (fromList [(5,"a"), (3,"b")]) == (3,"b") elemAt 1 (fromList [(5,"a"), (3,"b")]) == (5, "a") elemAt 2 (fromList [(5,"a"), (3,"b")]) Error: index out of range
deleteAt :: Int -> Map k a -> Map k a #
O(log n). Delete the element at index, i.e. by its zero-based index in
the sequence sorted by keys. If the index is out of range (less than zero,
greater or equal to size
of the map), error
is called.
deleteAt 0 (fromList [(5,"a"), (3,"b")]) == singleton 5 "a" deleteAt 1 (fromList [(5,"a"), (3,"b")]) == singleton 3 "b" deleteAt 2 (fromList [(5,"a"), (3,"b")]) Error: index out of range deleteAt (-1) (fromList [(5,"a"), (3,"b")]) Error: index out of range
findIndex :: Ord k => k -> Map k a -> Int #
O(log n). Return the index of a key, which is its zero-based index in
the sequence sorted by keys. The index is a number from 0 up to, but not
including, the size
of the map. Calls error
when the key is not
a member
of the map.
findIndex 2 (fromList [(5,"a"), (3,"b")]) Error: element is not in the map findIndex 3 (fromList [(5,"a"), (3,"b")]) == 0 findIndex 5 (fromList [(5,"a"), (3,"b")]) == 1 findIndex 6 (fromList [(5,"a"), (3,"b")]) Error: element is not in the map
updateAt :: (k -> a -> Maybe a) -> Int -> Map k a -> Map k a #
O(log n). Update the element at index. Calls error
when an
invalid index is used.
updateAt (\ _ _ -> Just "x") 0 (fromList [(5,"a"), (3,"b")]) == fromList [(3, "x"), (5, "a")] updateAt (\ _ _ -> Just "x") 1 (fromList [(5,"a"), (3,"b")]) == fromList [(3, "b"), (5, "x")] updateAt (\ _ _ -> Just "x") 2 (fromList [(5,"a"), (3,"b")]) Error: index out of range updateAt (\ _ _ -> Just "x") (-1) (fromList [(5,"a"), (3,"b")]) Error: index out of range updateAt (\_ _ -> Nothing) 0 (fromList [(5,"a"), (3,"b")]) == singleton 5 "a" updateAt (\_ _ -> Nothing) 1 (fromList [(5,"a"), (3,"b")]) == singleton 3 "b" updateAt (\_ _ -> Nothing) 2 (fromList [(5,"a"), (3,"b")]) Error: index out of range updateAt (\_ _ -> Nothing) (-1) (fromList [(5,"a"), (3,"b")]) Error: index out of range
Min/Max
findMin :: Map k a -> (k, a) #
O(log n). The minimal key of the map. Calls error
if the map is empty.
findMin (fromList [(5,"a"), (3,"b")]) == (3,"b") findMin empty Error: empty map has no minimal element
deleteFindMin :: Map k a -> ((k, a), Map k a) #
O(log n). Delete and find the minimal element.
deleteFindMin (fromList [(5,"a"), (3,"b"), (10,"c")]) == ((3,"b"), fromList[(5,"a"), (10,"c")]) deleteFindMin Error: can not return the minimal element of an empty map
deleteFindMax :: Map k a -> ((k, a), Map k a) #
O(log n). Delete and find the maximal element.
deleteFindMax (fromList [(5,"a"), (3,"b"), (10,"c")]) == ((10,"c"), fromList [(3,"b"), (5,"a")]) deleteFindMax empty Error: can not return the maximal element of an empty map