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Within LTS Haskell 24.35 (ghc-9.10.3)
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Opt_InfoTableMapWithStack :: GeneralFlagghc-lib-parser GHC.Driver.Session No documentation available.
ParMakeSemaphore :: FilePath -> ParMakeCountghc-lib-parser GHC.Driver.Session Use the specific semaphore sem to control parallelism (-jsem sem flag).
bitmap :: GenClosure b -> ![Word]ghc-lib-parser GHC.Exts.Heap An StgLargeBitmap describing the pointerhood of its args/free vars
bitmap :: GenClosure b -> ![Word]ghc-lib-parser GHC.Exts.Heap.Closures An StgLargeBitmap describing the pointerhood of its args/free vars
pExtsBitmap :: ParserOpts -> !ExtsBitmapghc-lib-parser GHC.Parser.Lexer bitmap of permitted extensions
rejectPragmaPV :: DisambECP b => LocatedA b -> PV ()ghc-lib-parser GHC.Parser.PostProcess Validate infixexp LHS to reject unwanted {-# SCC ... #-} pragmas
pc_BITMAP_BITS_SHIFT :: PlatformConstants -> {-# UNPACK #-} !Intghc-lib-parser GHC.Platform No documentation available.
pc_BITMAP_BITS_SHIFT :: PlatformConstants -> {-# UNPACK #-} !Intghc-lib-parser GHC.Platform.Constants No documentation available.
concatMap :: Foldable t => (a -> [b]) -> t a -> [b]ghc-lib-parser GHC.Prelude.Basic Map a function over all the elements of a container and concatenate the resulting lists.
Examples
Basic usage:>>> concatMap (take 3) [[1..], [10..], [100..], [1000..]] [1,2,3,10,11,12,100,101,102,1000,1001,1002]
>>> concatMap (take 3) (Just [1..]) [1,2,3]
fmap :: Functor f => (a -> b) -> f a -> f bghc-lib-parser GHC.Prelude.Basic fmap is used to apply a function of type (a -> b) to a value of type f a, where f is a functor, to produce a value of type f b. Note that for any type constructor with more than one parameter (e.g., Either), only the last type parameter can be modified with fmap (e.g., b in `Either a b`). Some type constructors with two parameters or more have a Bifunctor instance that allows both the last and the penultimate parameters to be mapped over.
Examples
Convert from a Maybe Int to a Maybe String using show:>>> fmap show Nothing Nothing >>> fmap show (Just 3) Just "3"
Convert from an Either Int Int to an Either Int String using show:>>> fmap show (Left 17) Left 17 >>> fmap show (Right 17) Right "17"
Double each element of a list:>>> fmap (*2) [1,2,3] [2,4,6]
Apply even to the second element of a pair:>>> fmap even (2,2) (2,True)
It may seem surprising that the function is only applied to the last element of the tuple compared to the list example above which applies it to every element in the list. To understand, remember that tuples are type constructors with multiple type parameters: a tuple of 3 elements (a,b,c) can also be written (,,) a b c and its Functor instance is defined for Functor ((,,) a b) (i.e., only the third parameter is free to be mapped over with fmap). It explains why fmap can be used with tuples containing values of different types as in the following example:>>> fmap even ("hello", 1.0, 4) ("hello",1.0,True)