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  1. gfoldMap1 :: (Foldable1 (Rep1 t), Generic1 t, Semigroup m) => (a -> m) -> t a -> m

    semigroupoids Data.Semigroup.Foldable

    Generic foldMap1. Caveats are the same as for gfold1.

  2. intercalateMap1 :: (Foldable1 t, Semigroup m) => m -> (a -> m) -> t a -> m

    semigroupoids Data.Semigroup.Foldable

    Insert m between each pair of m derived from a. 

    >>> intercalateMap1 " " show $ True :| [False, True]
"True False True"

    >>> intercalateMap1 " " show $ True :| []
"True"

  3. bifoldMap1 :: (Bifoldable1 t, Semigroup m) => (a -> m) -> (b -> m) -> t a b -> m

    semigroupoids Data.Semigroup.Foldable.Class

    No documentation available.

  4. foldMap1 :: (Foldable1 t, Semigroup m) => (a -> m) -> t a -> m

    semigroupoids Data.Semigroup.Foldable.Class

    Map each element of the structure to a semigroup, and combine the results with (<>). This fold is right-associative and lazy in the accumulator. For strict left-associative folds consider foldMap1' instead. 

    >>> foldMap1 (:[]) (1 :| [2, 3, 4])
[1,2,3,4]

  5. foldMap1Default :: (Traversable1 f, Semigroup m) => (a -> m) -> f a -> m

    semigroupoids Data.Semigroup.Traversable

    Default implementation of foldMap1 given an implementation of Traversable1.

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

    semigroupoids Semigroupoids.Do

    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)

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

    base-compat Data.Functor.Compat

    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)

  8. bifmap :: forall (p :: k -> k1 -> Type) (q :: k -> k1 -> Type) . BifunctorFunctor t => (p :-> q) -> t p :-> t q

    bifunctors Data.Bifunctor.Functor

    No documentation available.

  9. makeBifoldMap :: Name -> Q Exp

    bifunctors Data.Bifunctor.TH

    Generates a lambda expression which behaves like bifoldMap (without requiring a Bifoldable instance).

  10. makeBifoldMapOptions :: Options -> Name -> Q Exp

    bifunctors Data.Bifunctor.TH

    Like makeBifoldMap, but takes an Options argument.

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