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1. (|.|) :: ExpQ -> ExpQ -> ExpQ

   haskell-src-meta	Language.Haskell.Meta.Utils

   No documentation available.

2. ( #. ) :: Coercible c b => (b -> c) -> (a -> b) -> a -> c

   linear	Linear.Affine

   No documentation available.

3. (<.>) :: Numeric t => Vector t -> Vector t -> t

   hmatrix	Numeric.LinearAlgebra

   An infix synonym for dot

   >>> vector [1,2,3,4] <.> vector [-2,0,1,1]
   5.0
   

   >>> let 𝑖 = 0:+1 :: C
   
   >>> fromList [1+𝑖,1] <.> fromList [1,1+𝑖]
   2.0 :+ 0.0
   

4. (<.>) :: forall (n :: Nat) . KnownNat n => R n -> R n -> ℝ

   hmatrix	Numeric.LinearAlgebra.Static

   No documentation available.

5. data h :. t

   postgresql-simple	Database.PostgreSQL.Simple

   A composite type to parse your custom data structures without having to define dummy newtype wrappers every time.

   instance FromRow MyData where ...
   

   instance FromRow MyData2 where ...
   

   then I can do the following for free:

   res <- query' c "..."
   forM res $ \(MyData{..} :. MyData2{..}) -> do
   ....
   

6. (:.) :: h -> t -> (:.) h t

   postgresql-simple	Database.PostgreSQL.Simple

   No documentation available.

7. data h :. t

   postgresql-simple	Database.PostgreSQL.Simple.Types

   A composite type to parse your custom data structures without having to define dummy newtype wrappers every time.

   instance FromRow MyData where ...
   

   instance FromRow MyData2 where ...
   

   then I can do the following for free:

   res <- query' c "..."
   forM res $ \(MyData{..} :. MyData2{..}) -> do
   ....
   

8. (:.) :: h -> t -> (:.) h t

   postgresql-simple	Database.PostgreSQL.Simple.Types

   No documentation available.

9. (^.) :: s -> Getting a s a -> a

   rio	RIO

   (^.) applies a getter to a value; in other words, it gets a value out of a structure using a getter (which can be a lens, traversal, fold, etc.). Getting 1st field of a tuple:

   (^. _1) :: (a, b) -> a
   (^. _1) = fst
   

   When (^.) is used with a traversal, it combines all results using the Monoid instance for the resulting type. For instance, for lists it would be simple concatenation:

   >>> ("str","ing") ^. each
   "string"
   

   The reason for this is that traversals use Applicative, and the Applicative instance for Const uses monoid concatenation to combine “effects” of Const. A non-operator version of (^.) is called view, and it's a bit more general than (^.) (it works in MonadReader). If you need the general version, you can get it from microlens-mtl; otherwise there's view available in Lens.Micro.Extras.

10. (^..) :: s -> Getting (Endo [a]) s a -> [a]

    rio	RIO

    s ^.. t returns the list of all values that t gets from s. A Maybe contains either 0 or 1 values:

    >>> Just 3 ^.. _Just
    [3]
    

    Gathering all values in a list of tuples:

    >>> [(1,2),(3,4)] ^.. each.each
    [1,2,3,4]
    

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