| Copyright |
(c) Ross Paterson 2005
(c) Louis Wasserman 2009 (c) Bertram Felgenhauer David Feuer Ross Paterson and Milan Straka 2014 |
|---|---|
| License | BSD-style |
| Maintainer | libraries@haskell.org |
| Portability | portable |
| Safe Haskell | Trustworthy |
| Language | Haskell2010 |
Data.Sequence.Internal
Description
WARNING
This module is considered internal .
The Package Versioning Policy does not apply .
The contents of this module may change in any way whatsoever and without any warning between minor versions of this package.
Authors importing this module are expected to track development closely.
Description
General purpose finite sequences. Apart from being finite and having strict operations, sequences also differ from lists in supporting a wider variety of operations efficiently.
An amortized running time is given for each operation, with \( n \) referring to the length of the sequence and \( i \) being the integral index used by some operations. These bounds hold even in a persistent (shared) setting.
The implementation uses 2-3 finger trees annotated with sizes, as described in section 4.2 of
- Ralf Hinze and Ross Paterson, "Finger trees: a simple general-purpose data structure", Journal of Functional Programming 16:2 (2006) pp 197-217. http://staff.city.ac.uk/~ross/papers/FingerTree.html
Note
: Many of these operations have the same names as similar
operations on lists in the
Prelude
. The ambiguity may be resolved
using either qualification or the
hiding
clause.
Warning
: The size of a
Seq
must not exceed
maxBound::Int
. Violation
of this condition is not detected and if the size limit is exceeded, the
behaviour of the sequence is undefined. This is unlikely to occur in most
applications, but some care may be required when using
><
,
<*>
,
*>
, or
>>
, particularly repeatedly and particularly in combination with
replicate
or
fromFunction
.
Since: 0.5.9
Synopsis
-
newtype
Elem
a =
Elem
{
- getElem :: a
- data FingerTree a
- data Node a
- data Digit a
- class Sized a where
- class MaybeForce a
- newtype Seq a where
-
newtype
State
s a =
State
{
- runState :: s -> (s, a)
- execState :: State s a -> s -> a
- foldDigit :: (b -> b -> b) -> (a -> b) -> Digit a -> b
- foldNode :: (b -> b -> b) -> (a -> b) -> Node a -> b
- foldWithIndexDigit :: Sized a => (b -> b -> b) -> ( Int -> a -> b) -> Int -> Digit a -> b
- foldWithIndexNode :: Sized a => (m -> m -> m) -> ( Int -> a -> m) -> Int -> Node a -> m
- empty :: Seq a
- singleton :: a -> Seq a
- (<|) :: a -> Seq a -> Seq a
- (|>) :: Seq a -> a -> Seq a
- (><) :: Seq a -> Seq a -> Seq a
- fromList :: [a] -> Seq a
- fromFunction :: Int -> ( Int -> a) -> Seq a
- fromArray :: Ix i => Array i a -> Seq a
- replicate :: Int -> a -> Seq a
- replicateA :: Applicative f => Int -> f a -> f ( Seq a)
- replicateM :: Applicative m => Int -> m a -> m ( Seq a)
- cycleTaking :: Int -> Seq a -> Seq a
- iterateN :: Int -> (a -> a) -> a -> Seq a
- unfoldr :: (b -> Maybe (a, b)) -> b -> Seq a
- unfoldl :: (b -> Maybe (b, a)) -> b -> Seq a
- null :: Seq a -> Bool
- length :: Seq a -> Int
- data ViewL a
- viewl :: Seq a -> ViewL a
- data ViewR a
- viewr :: Seq a -> ViewR a
- scanl :: (a -> b -> a) -> a -> Seq b -> Seq a
- scanl1 :: (a -> a -> a) -> Seq a -> Seq a
- scanr :: (a -> b -> b) -> b -> Seq a -> Seq b
- scanr1 :: (a -> a -> a) -> Seq a -> Seq a
- tails :: Seq a -> Seq ( Seq a)
- inits :: Seq a -> Seq ( Seq a)
- chunksOf :: Int -> Seq a -> Seq ( Seq a)
- takeWhileL :: (a -> Bool ) -> Seq a -> Seq a
- takeWhileR :: (a -> Bool ) -> Seq a -> Seq a
- dropWhileL :: (a -> Bool ) -> Seq a -> Seq a
- dropWhileR :: (a -> Bool ) -> Seq a -> Seq a
- spanl :: (a -> Bool ) -> Seq a -> ( Seq a, Seq a)
- spanr :: (a -> Bool ) -> Seq a -> ( Seq a, Seq a)
- breakl :: (a -> Bool ) -> Seq a -> ( Seq a, Seq a)
- breakr :: (a -> Bool ) -> Seq a -> ( Seq a, Seq a)
- partition :: (a -> Bool ) -> Seq a -> ( Seq a, Seq a)
- filter :: (a -> Bool ) -> Seq a -> Seq a
- lookup :: Int -> Seq a -> Maybe a
- (!?) :: Seq a -> Int -> Maybe a
- index :: Seq a -> Int -> a
- adjust :: (a -> a) -> Int -> Seq a -> Seq a
- adjust' :: forall a. (a -> a) -> Int -> Seq a -> Seq a
- update :: Int -> a -> Seq a -> Seq a
- take :: Int -> Seq a -> Seq a
- drop :: Int -> Seq a -> Seq a
- insertAt :: Int -> a -> Seq a -> Seq a
- deleteAt :: Int -> Seq a -> Seq a
- splitAt :: Int -> Seq a -> ( Seq a, Seq a)
- elemIndexL :: Eq a => a -> Seq a -> Maybe Int
- elemIndicesL :: Eq a => a -> Seq a -> [ Int ]
- elemIndexR :: Eq a => a -> Seq a -> Maybe Int
- elemIndicesR :: Eq a => a -> Seq a -> [ Int ]
- findIndexL :: (a -> Bool ) -> Seq a -> Maybe Int
- findIndicesL :: (a -> Bool ) -> Seq a -> [ Int ]
- findIndexR :: (a -> Bool ) -> Seq a -> Maybe Int
- findIndicesR :: (a -> Bool ) -> Seq a -> [ Int ]
- foldMapWithIndex :: Monoid m => ( Int -> a -> m) -> Seq a -> m
- foldlWithIndex :: (b -> Int -> a -> b) -> b -> Seq a -> b
- foldrWithIndex :: ( Int -> a -> b -> b) -> b -> Seq a -> b
- mapWithIndex :: ( Int -> a -> b) -> Seq a -> Seq b
- traverseWithIndex :: Applicative f => ( Int -> a -> f b) -> Seq a -> f ( Seq b)
- reverse :: Seq a -> Seq a
- intersperse :: a -> Seq a -> Seq a
- liftA2Seq :: (a -> b -> c) -> Seq a -> Seq b -> Seq c
- zip :: Seq a -> Seq b -> Seq (a, b)
- zipWith :: (a -> b -> c) -> Seq a -> Seq b -> Seq c
- zip3 :: Seq a -> Seq b -> Seq c -> Seq (a, b, c)
- zipWith3 :: (a -> b -> c -> d) -> Seq a -> Seq b -> Seq c -> Seq d
- zip4 :: Seq a -> Seq b -> Seq c -> Seq d -> Seq (a, b, c, d)
- zipWith4 :: (a -> b -> c -> d -> e) -> Seq a -> Seq b -> Seq c -> Seq d -> Seq e
- unzip :: Seq (a, b) -> ( Seq a, Seq b)
- unzipWith :: (a -> (b, c)) -> Seq a -> ( Seq b, Seq c)
Documentation
Instances
data FingerTree a Source #
Instances
Instances
Instances
class MaybeForce a Source #
Minimal complete definition
maybeRwhnf
Instances
| MaybeForce ( Elem a) Source # | |
|
Defined in Data.Sequence.Internal Methods maybeRwhnf :: Elem a -> () |
|
| MaybeForce ( Node a) Source # | |
|
Defined in Data.Sequence.Internal Methods maybeRwhnf :: Node a -> () |
|
General-purpose finite sequences.
Constructors
| Seq ( FingerTree ( Elem a)) |
Bundled Patterns
| pattern Empty :: Seq a |
A bidirectional pattern synonym matching an empty sequence. Since: 0.5.8 |
| pattern (:<|) :: a -> Seq a -> Seq a infixr 5 |
A bidirectional pattern synonym viewing the front of a non-empty sequence. Since: 0.5.8 |
| pattern (:|>) :: Seq a -> a -> Seq a infixl 5 |
A bidirectional pattern synonym viewing the rear of a non-empty sequence. Since: 0.5.8 |
Instances
| Monad Seq Source # | |
| Functor Seq Source # | |
| MonadFix Seq Source # |
Since: 0.5.11 |
| Applicative Seq Source # |
Since: 0.5.4 |
| Foldable Seq Source # | |
|
Defined in Data.Sequence.Internal Methods fold :: Monoid m => Seq m -> m Source # foldMap :: Monoid m => (a -> m) -> Seq a -> m Source # foldMap' :: Monoid m => (a -> m) -> Seq a -> m Source # foldr :: (a -> b -> b) -> b -> Seq a -> b Source # foldr' :: (a -> b -> b) -> b -> Seq a -> b Source # foldl :: (b -> a -> b) -> b -> Seq a -> b Source # foldl' :: (b -> a -> b) -> b -> Seq a -> b Source # foldr1 :: (a -> a -> a) -> Seq a -> a Source # foldl1 :: (a -> a -> a) -> Seq a -> a Source # toList :: Seq a -> [a] Source # null :: Seq a -> Bool Source # length :: Seq a -> Int Source # elem :: Eq a => a -> Seq a -> Bool Source # maximum :: Ord a => Seq a -> a Source # minimum :: Ord a => Seq a -> a Source # |
|
| Traversable Seq Source # | |
| Eq1 Seq Source # |
Since: 0.5.9 |
| Ord1 Seq Source # |
Since: 0.5.9 |
|
Defined in Data.Sequence.Internal |
|
| Read1 Seq Source # |
Since: 0.5.9 |
|
Defined in Data.Sequence.Internal Methods liftReadsPrec :: ( Int -> ReadS a) -> ReadS [a] -> Int -> ReadS ( Seq a) Source # liftReadList :: ( Int -> ReadS a) -> ReadS [a] -> ReadS [ Seq a] Source # liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec ( Seq a) Source # liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [ Seq a] Source # |
|
| Show1 Seq Source # |
Since: 0.5.9 |
| MonadZip Seq Source # |
|
| Alternative Seq Source # |
Since: 0.5.4 |
| MonadPlus Seq Source # | |
| IsList ( Seq a) Source # | |
| Eq a => Eq ( Seq a) Source # | |
| Data a => Data ( Seq a) Source # | |
|
Defined in Data.Sequence.Internal Methods gfoldl :: ( forall d b. Data d => c (d -> b) -> d -> c b) -> ( forall g. g -> c g) -> Seq a -> c ( Seq a) Source # gunfold :: ( forall b r. Data b => c (b -> r) -> c r) -> ( forall r. r -> c r) -> Constr -> c ( Seq a) Source # toConstr :: Seq a -> Constr Source # dataTypeOf :: Seq a -> DataType Source # dataCast1 :: Typeable t => ( forall d. Data d => c (t d)) -> Maybe (c ( Seq a)) Source # dataCast2 :: Typeable t => ( forall d e. ( Data d, Data e) => c (t d e)) -> Maybe (c ( Seq a)) Source # gmapT :: ( forall b. Data b => b -> b) -> Seq a -> Seq a Source # gmapQl :: (r -> r' -> r) -> r -> ( forall d. Data d => d -> r') -> Seq a -> r Source # gmapQr :: forall r r'. (r' -> r -> r) -> r -> ( forall d. Data d => d -> r') -> Seq a -> r Source # gmapQ :: ( forall d. Data d => d -> u) -> Seq a -> [u] Source # gmapQi :: Int -> ( forall d. Data d => d -> u) -> Seq a -> u Source # gmapM :: Monad m => ( forall d. Data d => d -> m d) -> Seq a -> m ( Seq a) Source # gmapMp :: MonadPlus m => ( forall d. Data d => d -> m d) -> Seq a -> m ( Seq a) Source # gmapMo :: MonadPlus m => ( forall d. Data d => d -> m d) -> Seq a -> m ( Seq a) Source # |
|
| Ord a => Ord ( Seq a) Source # | |
|
Defined in Data.Sequence.Internal |
|
| Read a => Read ( Seq a) Source # | |
| Show a => Show ( Seq a) Source # | |
| a ~ Char => IsString ( Seq a) Source # |
Since: 0.5.7 |
|
Defined in Data.Sequence.Internal Methods fromString :: String -> Seq a Source # |
|
| Semigroup ( Seq a) Source # |
Since: 0.5.7 |
| Monoid ( Seq a) Source # | |
| NFData a => NFData ( Seq a) Source # | |
|
Defined in Data.Sequence.Internal |
|
| type Item ( Seq a) Source # | |
|
Defined in Data.Sequence.Internal |
|
Construction
(<|) :: a -> Seq a -> Seq a infixr 5 Source #
\( O(1) \) . Add an element to the left end of a sequence. Mnemonic: a triangle with the single element at the pointy end.
(|>) :: Seq a -> a -> Seq a infixl 5 Source #
\( O(1) \) . Add an element to the right end of a sequence. Mnemonic: a triangle with the single element at the pointy end.
(><) :: Seq a -> Seq a -> Seq a infixr 5 Source #
\( O(\log(\min(n_1,n_2))) \) . Concatenate two sequences.
fromFunction :: Int -> ( Int -> a) -> Seq a Source #
\( O(n) \) . Convert a given sequence length and a function representing that sequence into a sequence.
Since: 0.5.6.2
fromArray :: Ix i => Array i a -> Seq a Source #
\( O(n) \)
. Create a sequence consisting of the elements of an
Array
.
Note that the resulting sequence elements may be evaluated lazily (as on GHC),
so you must force the entire structure to be sure that the original array
can be garbage-collected.
Since: 0.5.6.2
Repetition
replicate :: Int -> a -> Seq a Source #
\( O(\log n) \)
.
replicate n x
is a sequence consisting of
n
copies of
x
.
replicateA :: Applicative f => Int -> f a -> f ( Seq a) Source #
replicateA
is an
Applicative
version of
replicate
, and makes
\( O(\log n) \)
calls to
liftA2
and
pure
.
replicateA n x = sequenceA (replicate n x)
replicateM :: Applicative m => Int -> m a -> m ( Seq a) Source #
replicateM
is a sequence counterpart of
replicateM
.
replicateM n x = sequence (replicate n x)
For
base >= 4.8.0
and
containers >= 0.5.11
,
replicateM
is a synonym for
replicateA
.
cycleTaking :: Int -> Seq a -> Seq a Source #
O(
log
k)
.
forms a sequence of length
cycleTaking
k xs
k
by
repeatedly concatenating
xs
with itself.
xs
may only be empty if
k
is 0.
cycleTaking k = fromList . take k . cycle . toList
Iterative construction
iterateN :: Int -> (a -> a) -> a -> Seq a Source #
\( O(n) \) . Constructs a sequence by repeated application of a function to a seed value.
iterateN n f x = fromList (Prelude.take n (Prelude.iterate f x))
unfoldr :: (b -> Maybe (a, b)) -> b -> Seq a Source #
Builds a sequence from a seed value. Takes time linear in the number of generated elements. WARNING: If the number of generated elements is infinite, this method will not terminate.
Deconstruction
Queries
Views
View of the left end of a sequence.
Constructors
| EmptyL |
empty sequence |
| a :< ( Seq a) infixr 5 |
leftmost element and the rest of the sequence |
Instances
| Functor ViewL Source # | |
| Foldable ViewL Source # | |
|
Defined in Data.Sequence.Internal Methods fold :: Monoid m => ViewL m -> m Source # foldMap :: Monoid m => (a -> m) -> ViewL a -> m Source # foldMap' :: Monoid m => (a -> m) -> ViewL a -> m Source # foldr :: (a -> b -> b) -> b -> ViewL a -> b Source # foldr' :: (a -> b -> b) -> b -> ViewL a -> b Source # foldl :: (b -> a -> b) -> b -> ViewL a -> b Source # foldl' :: (b -> a -> b) -> b -> ViewL a -> b Source # foldr1 :: (a -> a -> a) -> ViewL a -> a Source # foldl1 :: (a -> a -> a) -> ViewL a -> a Source # toList :: ViewL a -> [a] Source # null :: ViewL a -> Bool Source # length :: ViewL a -> Int Source # elem :: Eq a => a -> ViewL a -> Bool Source # maximum :: Ord a => ViewL a -> a Source # minimum :: Ord a => ViewL a -> a Source # |
|
| Traversable ViewL Source # | |
|
Defined in Data.Sequence.Internal |
|
| Eq a => Eq ( ViewL a) Source # | |
| Data a => Data ( ViewL a) Source # | |
|
Defined in Data.Sequence.Internal Methods gfoldl :: ( forall d b. Data d => c (d -> b) -> d -> c b) -> ( forall g. g -> c g) -> ViewL a -> c ( ViewL a) Source # gunfold :: ( forall b r. Data b => c (b -> r) -> c r) -> ( forall r. r -> c r) -> Constr -> c ( ViewL a) Source # toConstr :: ViewL a -> Constr Source # dataTypeOf :: ViewL a -> DataType Source # dataCast1 :: Typeable t => ( forall d. Data d => c (t d)) -> Maybe (c ( ViewL a)) Source # dataCast2 :: Typeable t => ( forall d e. ( Data d, Data e) => c (t d e)) -> Maybe (c ( ViewL a)) Source # gmapT :: ( forall b. Data b => b -> b) -> ViewL a -> ViewL a Source # gmapQl :: (r -> r' -> r) -> r -> ( forall d. Data d => d -> r') -> ViewL a -> r Source # gmapQr :: forall r r'. (r' -> r -> r) -> r -> ( forall d. Data d => d -> r') -> ViewL a -> r Source # gmapQ :: ( forall d. Data d => d -> u) -> ViewL a -> [u] Source # gmapQi :: Int -> ( forall d. Data d => d -> u) -> ViewL a -> u Source # gmapM :: Monad m => ( forall d. Data d => d -> m d) -> ViewL a -> m ( ViewL a) Source # gmapMp :: MonadPlus m => ( forall d. Data d => d -> m d) -> ViewL a -> m ( ViewL a) Source # gmapMo :: MonadPlus m => ( forall d. Data d => d -> m d) -> ViewL a -> m ( ViewL a) Source # |
|
| Ord a => Ord ( ViewL a) Source # | |
|
Defined in Data.Sequence.Internal |
|
| Read a => Read ( ViewL a) Source # | |
| Show a => Show ( ViewL a) Source # | |
| Generic ( ViewL a) Source # |
Since: 0.5.8 |
| Generic1 ViewL Source # |
Since: 0.5.8 |
| type Rep ( ViewL a) Source # | |
|
Defined in Data.Sequence.Internal
type
Rep
(
ViewL
a) =
D1
('
MetaData
"ViewL" "Data.Sequence.Internal" "containers-0.6.5.1-EiES0HFUZ8PBGNrpVjoYRF" '
False
) (
C1
('
MetaCons
"EmptyL" '
PrefixI
'
False
) (
U1
::
Type
->
Type
)
:+:
C1
('
MetaCons
":<" ('
InfixI
'
RightAssociative
5) '
False
) (
S1
('
MetaSel
('
Nothing
::
Maybe
Symbol
) '
NoSourceUnpackedness
'
NoSourceStrictness
'
DecidedLazy
) (
Rec0
a)
:*:
S1
('
MetaSel
('
Nothing
::
Maybe
Symbol
) '
NoSourceUnpackedness
'
NoSourceStrictness
'
DecidedLazy
) (
Rec0
(
Seq
a))))
|
|
| type Rep1 ViewL Source # | |
|
Defined in Data.Sequence.Internal
type
Rep1
ViewL
=
D1
('
MetaData
"ViewL" "Data.Sequence.Internal" "containers-0.6.5.1-EiES0HFUZ8PBGNrpVjoYRF" '
False
) (
C1
('
MetaCons
"EmptyL" '
PrefixI
'
False
) (
U1
::
Type
->
Type
)
:+:
C1
('
MetaCons
":<" ('
InfixI
'
RightAssociative
5) '
False
) (
S1
('
MetaSel
('
Nothing
::
Maybe
Symbol
) '
NoSourceUnpackedness
'
NoSourceStrictness
'
DecidedLazy
)
Par1
:*:
S1
('
MetaSel
('
Nothing
::
Maybe
Symbol
) '
NoSourceUnpackedness
'
NoSourceStrictness
'
DecidedLazy
) (
Rec1
Seq
)))
|
|
View of the right end of a sequence.
Constructors
| EmptyR |
empty sequence |
| ( Seq a) :> a infixl 5 |
the sequence minus the rightmost element, and the rightmost element |
Instances
| Functor ViewR Source # | |
| Foldable ViewR Source # | |
|
Defined in Data.Sequence.Internal Methods fold :: Monoid m => ViewR m -> m Source # foldMap :: Monoid m => (a -> m) -> ViewR a -> m Source # foldMap' :: Monoid m => (a -> m) -> ViewR a -> m Source # foldr :: (a -> b -> b) -> b -> ViewR a -> b Source # foldr' :: (a -> b -> b) -> b -> ViewR a -> b Source # foldl :: (b -> a -> b) -> b -> ViewR a -> b Source # foldl' :: (b -> a -> b) -> b -> ViewR a -> b Source # foldr1 :: (a -> a -> a) -> ViewR a -> a Source # foldl1 :: (a -> a -> a) -> ViewR a -> a Source # toList :: ViewR a -> [a] Source # null :: ViewR a -> Bool Source # length :: ViewR a -> Int Source # elem :: Eq a => a -> ViewR a -> Bool Source # maximum :: Ord a => ViewR a -> a Source # minimum :: Ord a => ViewR a -> a Source # |
|
| Traversable ViewR Source # | |
|
Defined in Data.Sequence.Internal |
|
| Eq a => Eq ( ViewR a) Source # | |
| Data a => Data ( ViewR a) Source # | |
|
Defined in Data.Sequence.Internal Methods gfoldl :: ( forall d b. Data d => c (d -> b) -> d -> c b) -> ( forall g. g -> c g) -> ViewR a -> c ( ViewR a) Source # gunfold :: ( forall b r. Data b => c (b -> r) -> c r) -> ( forall r. r -> c r) -> Constr -> c ( ViewR a) Source # toConstr :: ViewR a -> Constr Source # dataTypeOf :: ViewR a -> DataType Source # dataCast1 :: Typeable t => ( forall d. Data d => c (t d)) -> Maybe (c ( ViewR a)) Source # dataCast2 :: Typeable t => ( forall d e. ( Data d, Data e) => c (t d e)) -> Maybe (c ( ViewR a)) Source # gmapT :: ( forall b. Data b => b -> b) -> ViewR a -> ViewR a Source # gmapQl :: (r -> r' -> r) -> r -> ( forall d. Data d => d -> r') -> ViewR a -> r Source # gmapQr :: forall r r'. (r' -> r -> r) -> r -> ( forall d. Data d => d -> r') -> ViewR a -> r Source # gmapQ :: ( forall d. Data d => d -> u) -> ViewR a -> [u] Source # gmapQi :: Int -> ( forall d. Data d => d -> u) -> ViewR a -> u Source # gmapM :: Monad m => ( forall d. Data d => d -> m d) -> ViewR a -> m ( ViewR a) Source # gmapMp :: MonadPlus m => ( forall d. Data d => d -> m d) -> ViewR a -> m ( ViewR a) Source # gmapMo :: MonadPlus m => ( forall d. Data d => d -> m d) -> ViewR a -> m ( ViewR a) Source # |
|
| Ord a => Ord ( ViewR a) Source # | |
|
Defined in Data.Sequence.Internal |
|
| Read a => Read ( ViewR a) Source # | |
| Show a => Show ( ViewR a) Source # | |
| Generic ( ViewR a) Source # |
Since: 0.5.8 |
| Generic1 ViewR Source # |
Since: 0.5.8 |
| type Rep ( ViewR a) Source # | |
|
Defined in Data.Sequence.Internal
type
Rep
(
ViewR
a) =
D1
('
MetaData
"ViewR" "Data.Sequence.Internal" "containers-0.6.5.1-EiES0HFUZ8PBGNrpVjoYRF" '
False
) (
C1
('
MetaCons
"EmptyR" '
PrefixI
'
False
) (
U1
::
Type
->
Type
)
:+:
C1
('
MetaCons
":>" ('
InfixI
'
LeftAssociative
5) '
False
) (
S1
('
MetaSel
('
Nothing
::
Maybe
Symbol
) '
NoSourceUnpackedness
'
NoSourceStrictness
'
DecidedLazy
) (
Rec0
(
Seq
a))
:*:
S1
('
MetaSel
('
Nothing
::
Maybe
Symbol
) '
NoSourceUnpackedness
'
NoSourceStrictness
'
DecidedLazy
) (
Rec0
a)))
|
|
| type Rep1 ViewR Source # | |
|
Defined in Data.Sequence.Internal
type
Rep1
ViewR
=
D1
('
MetaData
"ViewR" "Data.Sequence.Internal" "containers-0.6.5.1-EiES0HFUZ8PBGNrpVjoYRF" '
False
) (
C1
('
MetaCons
"EmptyR" '
PrefixI
'
False
) (
U1
::
Type
->
Type
)
:+:
C1
('
MetaCons
":>" ('
InfixI
'
LeftAssociative
5) '
False
) (
S1
('
MetaSel
('
Nothing
::
Maybe
Symbol
) '
NoSourceUnpackedness
'
NoSourceStrictness
'
DecidedLazy
) (
Rec1
Seq
)
:*:
S1
('
MetaSel
('
Nothing
::
Maybe
Symbol
) '
NoSourceUnpackedness
'
NoSourceStrictness
'
DecidedLazy
)
Par1
))
|
|
Scans
Sublists
tails :: Seq a -> Seq ( Seq a) Source #
\( O(n) \) . Returns a sequence of all suffixes of this sequence, longest first. For example,
tails (fromList "abc") = fromList [fromList "abc", fromList "bc", fromList "c", fromList ""]
Evaluating the \( i \) th suffix takes \( O(\log(\min(i, n-i))) \) , but evaluating every suffix in the sequence takes \( O(n) \) due to sharing.
inits :: Seq a -> Seq ( Seq a) Source #
\( O(n) \) . Returns a sequence of all prefixes of this sequence, shortest first. For example,
inits (fromList "abc") = fromList [fromList "", fromList "a", fromList "ab", fromList "abc"]
Evaluating the \( i \) th prefix takes \( O(\log(\min(i, n-i))) \) , but evaluating every prefix in the sequence takes \( O(n) \) due to sharing.
chunksOf :: Int -> Seq a -> Seq ( Seq a) Source #
\(O \Bigl(\bigl(\frac{n}{c}\bigr) \log c\Bigr)\)
.
chunksOf c xs
splits
xs
into chunks of size
c>0
.
If
c
does not divide the length of
xs
evenly, then the last element
of the result will be short.
Side note: the given performance bound is missing some messy terms that only really affect edge cases. Performance degrades smoothly from \( O(1) \) (for \( c = n \) ) to \( O(n) \) (for \( c = 1 \) ). The true bound is more like \( O \Bigl( \bigl(\frac{n}{c} - 1\bigr) (\log (c + 1)) + 1 \Bigr) \)
Since: 0.5.8
Sequential searches
takeWhileL :: (a -> Bool ) -> Seq a -> Seq a Source #
\( O(i) \)
where
\( i \)
is the prefix length.
takeWhileL
, applied
to a predicate
p
and a sequence
xs
, returns the longest prefix
(possibly empty) of
xs
of elements that satisfy
p
.
takeWhileR :: (a -> Bool ) -> Seq a -> Seq a Source #
\( O(i) \)
where
\( i \)
is the suffix length.
takeWhileR
, applied
to a predicate
p
and a sequence
xs
, returns the longest suffix
(possibly empty) of
xs
of elements that satisfy
p
.
is equivalent to
takeWhileR
p xs
.
reverse
(
takeWhileL
p (
reverse
xs))
dropWhileL :: (a -> Bool ) -> Seq a -> Seq a Source #
\( O(i) \)
where
\( i \)
is the prefix length.
returns
the suffix remaining after
dropWhileL
p xs
.
takeWhileL
p xs
dropWhileR :: (a -> Bool ) -> Seq a -> Seq a Source #
\( O(i) \)
where
\( i \)
is the suffix length.
returns
the prefix remaining after
dropWhileR
p xs
.
takeWhileR
p xs
is equivalent to
dropWhileR
p xs
.
reverse
(
dropWhileL
p (
reverse
xs))
spanl :: (a -> Bool ) -> Seq a -> ( Seq a, Seq a) Source #
\( O(i) \)
where
\( i \)
is the prefix length.
spanl
, applied to
a predicate
p
and a sequence
xs
, returns a pair whose first
element is the longest prefix (possibly empty) of
xs
of elements that
satisfy
p
and the second element is the remainder of the sequence.
spanr :: (a -> Bool ) -> Seq a -> ( Seq a, Seq a) Source #
\( O(i) \)
where
\( i \)
is the suffix length.
spanr
, applied to a
predicate
p
and a sequence
xs
, returns a pair whose
first
element
is the longest
suffix
(possibly empty) of
xs
of elements that
satisfy
p
and the second element is the remainder of the sequence.
breakl :: (a -> Bool ) -> Seq a -> ( Seq a, Seq a) Source #
\( O(i) \)
where
\( i \)
is the breakpoint index.
breakl
, applied to a
predicate
p
and a sequence
xs
, returns a pair whose first element
is the longest prefix (possibly empty) of
xs
of elements that
do not satisfy
p
and the second element is the remainder of
the sequence.
partition :: (a -> Bool ) -> Seq a -> ( Seq a, Seq a) Source #
\( O(n) \)
. The
partition
function takes a predicate
p
and a
sequence
xs
and returns sequences of those elements which do and
do not satisfy the predicate.
filter :: (a -> Bool ) -> Seq a -> Seq a Source #
\( O(n) \)
. The
filter
function takes a predicate
p
and a sequence
xs
and returns a sequence of those elements which satisfy the
predicate.
Indexing
lookup :: Int -> Seq a -> Maybe a Source #
\( O(\log(\min(i,n-i))) \)
. The element at the specified position,
counting from 0. If the specified position is negative or at
least the length of the sequence,
lookup
returns
Nothing
.
0 <= i < length xs ==> lookup i xs == Just (toList xs !! i)
i < 0 || i >= length xs ==> lookup i xs = Nothing
Unlike
index
, this can be used to retrieve an element without
forcing it. For example, to insert the fifth element of a sequence
xs
into a
Map
m
at key
k
, you could use
case lookup 5 xs of
Nothing -> m
Just x -> insert k x m
Since: 0.5.8
(!?) :: Seq a -> Int -> Maybe a Source #
\( O(\log(\min(i,n-i))) \)
. A flipped, infix version of
lookup
.
Since: 0.5.8
index :: Seq a -> Int -> a Source #
\( O(\log(\min(i,n-i))) \)
. The element at the specified position,
counting from 0. The argument should thus be a non-negative
integer less than the size of the sequence.
If the position is out of range,
index
fails with an error.
xs `index` i = toList xs !! i
Caution:
index
necessarily delays retrieving the requested
element until the result is forced. It can therefore lead to a space
leak if the result is stored, unforced, in another structure. To retrieve
an element immediately without forcing it, use
lookup
or
(!?)
.
adjust :: (a -> a) -> Int -> Seq a -> Seq a Source #
\( O(\log(\min(i,n-i))) \)
. 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.
Since: 0.5.8
adjust' :: forall a. (a -> a) -> Int -> Seq a -> Seq a Source #
\( O(\log(\min(i,n-i))) \) . 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
Since: 0.5.8
update :: Int -> a -> Seq a -> Seq a Source #
\( O(\log(\min(i,n-i))) \) . Replace the element at the specified position. If the position is out of range, the original sequence is returned.
take :: Int -> Seq a -> Seq a Source #
\( O(\log(\min(i,n-i))) \)
. The first
i
elements of a sequence.
If
i
is negative,
yields the empty sequence.
If the sequence contains fewer than
take
i s
i
elements, the whole sequence
is returned.
drop :: Int -> Seq a -> Seq a Source #
\( O(\log(\min(i,n-i))) \)
. Elements of a sequence after the first
i
.
If
i
is negative,
yields the whole sequence.
If the sequence contains fewer than
drop
i s
i
elements, the empty sequence
is returned.
insertAt :: Int -> a -> Seq a -> Seq a Source #
\( O(\log(\min(i,n-i))) \)
.
inserts
insertAt
i x xs
x
into
xs
at the index
i
, shifting the rest of the sequence over.
insertAt 2 x (fromList [a,b,c,d]) = fromList [a,b,x,c,d]
insertAt 4 x (fromList [a,b,c,d]) = insertAt 10 x (fromList [a,b,c,d])
= fromList [a,b,c,d,x]
insertAt i x xs = take i xs >< singleton x >< drop i xs
Since: 0.5.8
deleteAt :: Int -> Seq a -> Seq a Source #
\( O(\log(\min(i,n-i))) \) . Delete the element of a sequence at a given index. Return the original sequence if the index is out of range.
deleteAt 2 [a,b,c,d] = [a,b,d] deleteAt 4 [a,b,c,d] = deleteAt (-1) [a,b,c,d] = [a,b,c,d]
Since: 0.5.8
Indexing with predicates
These functions perform sequential searches from the left or right ends of the sequence, returning indices of matching elements.
elemIndexL :: Eq a => a -> Seq a -> Maybe Int Source #
elemIndexL
finds the leftmost index of the specified element,
if it is present, and otherwise
Nothing
.
elemIndicesL :: Eq a => a -> Seq a -> [ Int ] Source #
elemIndicesL
finds the indices of the specified element, from
left to right (i.e. in ascending order).
elemIndexR :: Eq a => a -> Seq a -> Maybe Int Source #
elemIndexR
finds the rightmost index of the specified element,
if it is present, and otherwise
Nothing
.
elemIndicesR :: Eq a => a -> Seq a -> [ Int ] Source #
elemIndicesR
finds the indices of the specified element, from
right to left (i.e. in descending order).
findIndexL :: (a -> Bool ) -> Seq a -> Maybe Int Source #
finds the index of the leftmost element that
satisfies
findIndexL
p xs
p
, if any exist.
findIndicesL :: (a -> Bool ) -> Seq a -> [ Int ] Source #
finds all indices of elements that satisfy
findIndicesL
p
p
,
in ascending order.
findIndexR :: (a -> Bool ) -> Seq a -> Maybe Int Source #
finds the index of the rightmost element that
satisfies
findIndexR
p xs
p
, if any exist.
findIndicesR :: (a -> Bool ) -> Seq a -> [ Int ] Source #
finds all indices of elements that satisfy
findIndicesR
p
p
,
in descending order.
Folds
foldlWithIndex :: (b -> Int -> a -> b) -> b -> Seq a -> b Source #
foldlWithIndex
is a version of
foldl
that also provides access
to the index of each element.
foldrWithIndex :: ( Int -> a -> b -> b) -> b -> Seq a -> b Source #
foldrWithIndex
is a version of
foldr
that also provides access
to the index of each element.
Transformations
mapWithIndex :: ( Int -> a -> b) -> Seq a -> Seq b Source #
A generalization of
fmap
,
mapWithIndex
takes a mapping
function that also depends on the element's index, and applies it to every
element in the sequence.
traverseWithIndex :: Applicative f => ( Int -> a -> f b) -> Seq a -> f ( Seq b) Source #
traverseWithIndex
is a version of
traverse
that also offers
access to the index of each element.
Since: 0.5.8
intersperse :: a -> Seq a -> Seq a Source #
\( O(n) \) . Intersperse an element between the elements of a sequence.
intersperse a empty = empty intersperse a (singleton x) = singleton x intersperse a (fromList [x,y]) = fromList [x,a,y] intersperse a (fromList [x,y,z]) = fromList [x,a,y,a,z]
Since: 0.5.8
Zips and unzips
zip :: Seq a -> Seq b -> Seq (a, b) Source #
\( O(\min(n_1,n_2)) \)
.
zip
takes two sequences and returns a sequence
of corresponding pairs. If one input is short, excess elements are
discarded from the right end of the longer sequence.
unzipWith :: (a -> (b, c)) -> Seq a -> ( Seq b, Seq c) Source #
\( O(n) \) . Unzip a sequence using a function to divide elements.
unzipWith f xs ==unzip(fmapf xs)
Efficiency note:
unzipWith
produces its two results in lockstep. If you calculate
unzipWith f xs
and fully force
either
of the results, then the
entire structure of the
other
one will be built as well. This
behavior allows the garbage collector to collect each calculated
pair component as soon as it dies, without having to wait for its mate
to die. If you do not need this behavior, you may be better off simply
calculating the sequence of pairs and using
fmap
to extract each
component sequence.
Since: 0.5.11