Modulelens-5.3.5Haskell2010

Data.Sequence.Lens

6 values

Packagelens-5.3.5
Exports6
LanguageHaskell2010
LicenceBSD-2-Clause
SourceLens.hs

valueviewL

:: (Profunctor p, Functor f)
=> p (ViewL a) (f (ViewL b))
-> p (Seq a) (f (Seq b))

A Seq is isomorphic to a ViewL

viewl m ≡ m ^. viewL

Example1 expression

>>> Seq.fromList [a,b,c] ^. viewLa :< fromList [b,c]

Example1 expression

>>> Seq.empty ^. viewLEmptyL

Example1 expression

>>> EmptyL ^. from viewLfromList []

Example1 expression

>>> review viewL $ a Seq.:< Seq.fromList [b,c]fromList [a,b,c]

valueviewR

:: (Profunctor p, Functor f)
=> p (ViewR a) (f (ViewR b))
-> p (Seq a) (f (Seq b))

A Seq is isomorphic to a ViewR

viewr m ≡ m ^. viewR

Example1 expression

>>> Seq.fromList [a,b,c] ^. viewRfromList [a,b] :> c

Example1 expression

>>> Seq.empty ^. viewREmptyR

Example1 expression

>>> EmptyR ^. from viewRfromList []

Example1 expression

>>> review viewR $ Seq.fromList [a,b] Seq.:> cfromList [a,b,c]

valuesliced :: Int -> Int -> IndexedTraversal' Int (Seq a) a

Traverse all the elements numbered from i to j of a Seq

Example1 expression

>>> Seq.fromList [a,b,c,d,e] & sliced 1 3 %~ ffromList [a,f b,f c,d,e]

valueslicedTo :: Int -> IndexedTraversal' Int (Seq a) a

Traverse the first n elements of a Seq

Example1 expression

>>> Seq.fromList [a,b,c,d,e] ^.. slicedTo 2[a,b]

Example1 expression

>>> Seq.fromList [a,b,c,d,e] & slicedTo 2 %~ ffromList [f a,f b,c,d,e]

Example1 expression

>>> Seq.fromList [a,b,c,d,e] & slicedTo 10 .~ xfromList [x,x,x,x,x]

valueslicedFrom :: Int -> IndexedTraversal' Int (Seq a) a

Traverse all but the first n elements of a Seq

Example1 expression

>>> Seq.fromList [a,b,c,d,e] ^.. slicedFrom 2[c,d,e]

Example1 expression

>>> Seq.fromList [a,b,c,d,e] & slicedFrom 2 %~ ffromList [a,b,f c,f d,f e]

Example1 expression

>>> Seq.fromList [a,b,c,d,e] & slicedFrom 10 .~ xfromList [a,b,c,d,e]

valueseqOf :: Getting (Seq a) s a -> s -> Seq a

Construct a Seq from a Getter, Fold, Control.Lens.Traversal.Traversal, Control.Lens.Lens.Lens or Control.Lens.Iso.Iso.

Example1 expression

>>> seqOf folded ["hello","world"]fromList ["hello","world"]

Example1 expression

>>> seqOf (folded._2) [("hello",1),("world",2),("!!!",3)]fromList [1,2,3]

seqOf :: Getter s a    -> s -> Seq a
seqOf :: Fold s a      -> s -> Seq a
seqOf :: Iso' s a       -> s -> Seq a
seqOf :: Lens' s a      -> s -> Seq a
seqOf :: Traversal' s a -> s -> Seq a