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  1. concatMapFoldableWith :: forall t f (m :: Type -> Type) b a . (IsStream t, Foldable f) => (t m b -> t m b -> t m b) -> (a -> t m b) -> f a -> t m b

    streamly Streamly.Prelude

    A variant of foldMap that allows you to map a monadic streaming action on a Foldable container and then fold it using the specified stream merge operation. 

    concatMapFoldableWith async return [1..3]
    Equivalent to: 
    concatMapFoldableWith f g = Prelude.foldr (f . g) S.nil
concatMapFoldableWith f g xs = S.concatMapWith f g (S.fromFoldable xs)
    Since: 0.8.0 (Renamed foldMapWith to concatMapFoldableWith) Since: 0.1.0 (Streamly)

  2. concatMapM :: (IsStream t, Monad m) => (a -> m (t m b)) -> t m a -> t m b

    streamly Streamly.Prelude

    Map a stream producing monadic function on each element of the stream and then flatten the results into a single stream. Since the stream generation function is monadic, unlike concatMap, it can produce an effect at the beginning of each iteration of the inner loop.

  3. concatMapWith :: forall t (m :: Type -> Type) b a . IsStream t => (t m b -> t m b -> t m b) -> (a -> t m b) -> t m a -> t m b

    streamly Streamly.Prelude

    concatMapWith mixer generator stream is a two dimensional looping combinator. The generator function is used to generate streams from the elements in the input stream and the mixer function is used to merge those streams. Note we can merge streams concurrently by using a concurrent merge function. Since: 0.7.0 Since: 0.8.0 (signature change)

  4. constrainedFmap :: forall r t (o :: Type -> Constraint) a b f . (Category r, Category t, o a, o b, o (f a), o (f b)) => (r a b -> t (f a) (f b)) -> (o ⊢ r) a b -> (o ⊢ t) (f a) (f b)

    constrained-categories Control.Category.Constrained.Prelude

    No documentation available.

  5. fmap :: (Functor f r t, Object r a, Object t (f a), Object r b, Object t (f b)) => r a b -> t (f a) (f b)

    constrained-categories Control.Category.Constrained.Prelude

    No documentation available.

  6. genericAgentMap :: (HasAgent k, Object k a, Object k b, Object k c) => k b c -> GenericAgent k a b -> GenericAgent k a c

    constrained-categories Control.Category.Constrained.Prelude

    No documentation available.

  7. concatMap :: Foldable t => (a -> [b]) -> t a -> [b]

    copilot-language Copilot.Language.Prelude

    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]

  8. fmap :: Functor f => (a -> b) -> f a -> f b

    copilot-language Copilot.Language.Prelude

    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)

  9. foldMap :: (Foldable t, Monoid m) => (a -> m) -> t a -> m

    copilot-language Copilot.Language.Prelude

    Map each element of the structure into a monoid, and combine the results with (<>). This fold is right-associative and lazy in the accumulator. For strict left-associative folds consider foldMap' instead.

    Examples

    Basic usage: 
    >>> foldMap Sum [1, 3, 5]
Sum {getSum = 9}

    >>> foldMap Product [1, 3, 5]
Product {getProduct = 15}

    >>> foldMap (replicate 3) [1, 2, 3]
[1,1,1,2,2,2,3,3,3]
    When a Monoid's (<>) is lazy in its second argument, foldMap can return a result even from an unbounded structure. For example, lazy accumulation enables Data.ByteString.Builder to efficiently serialise large data structures and produce the output incrementally: 
    >>> import qualified Data.ByteString.Lazy as L

>>> import qualified Data.ByteString.Builder as B

>>> let bld :: Int -> B.Builder; bld i = B.intDec i <> B.word8 0x20

>>> let lbs = B.toLazyByteString $ foldMap bld [0..]

>>> L.take 64 lbs
"0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24"

  10. concatMap :: Foldable t => (a -> [b]) -> t a -> [b]

    xmonad-contrib XMonad.Prelude

    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]

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