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1. head :: HasCallStack => [a] -> a

   constrained-categories	Control.Category.Constrained.Prelude

   Extract the first element of a list, which must be non-empty. To disable the warning about partiality put {-# OPTIONS_GHC -Wno-x-partial -Wno-unrecognised-warning-flags #-} at the top of the file. To disable it throughout a package put the same options into ghc-options section of Cabal file. To disable it in GHCi put :set -Wno-x-partial -Wno-unrecognised-warning-flags into ~/.ghci config file. See also the migration guide.

   Examples

   >>> head [1, 2, 3]
   1
   

   >>> head [1..]
   1
   

   >>> head []
   *** Exception: Prelude.head: empty list
   

2. head :: HasCallStack => [a] -> a

   constrained-categories	Control.Category.Hask

   Extract the first element of a list, which must be non-empty. To disable the warning about partiality put {-# OPTIONS_GHC -Wno-x-partial -Wno-unrecognised-warning-flags #-} at the top of the file. To disable it throughout a package put the same options into ghc-options section of Cabal file. To disable it in GHCi put :set -Wno-x-partial -Wno-unrecognised-warning-flags into ~/.ghci config file. See also the migration guide.

   Examples

   >>> head [1, 2, 3]
   1
   

   >>> head [1..]
   1
   

   >>> head []
   *** Exception: Prelude.head: empty list
   

3. head :: HasCallStack => [a] -> a

   copilot-language	Copilot.Language.Prelude

   Extract the first element of a list, which must be non-empty. To disable the warning about partiality put {-# OPTIONS_GHC -Wno-x-partial -Wno-unrecognised-warning-flags #-} at the top of the file. To disable it throughout a package put the same options into ghc-options section of Cabal file. To disable it in GHCi put :set -Wno-x-partial -Wno-unrecognised-warning-flags into ~/.ghci config file. See also the migration guide.

   Examples

   >>> head [1, 2, 3]
   1
   

   >>> head [1..]
   1
   

   >>> head []
   *** Exception: Prelude.head: empty list
   

4. head :: ToElem a => a -> Perch

   ghcjs-perch	GHCJS.Perch

   No documentation available.

5. head :: forall (u :: Type -> Type) a (v :: Type -> Type) b . (Vector u a, Vector v b) => Vector u v (a, b) -> (a, b)

   hybrid-vectors	Data.Vector.Hybrid

   O(1) First element

6. head :: MonadThrow m => [a] -> m a

   listsafe	Data.List.Safe

   Extract the first element of a list. Empty lists throw an EmptyListException.

7. head :: (Functor f, HasField s "head" a) => LensLike' f s a

   riak-protobuf	Data.Riak.Proto

   No documentation available.

8. head :: StringCells s => s -> StringCellChar s

   string-class	Data.String.Class

   No documentation available.

9. head :: NonEmpty a -> a

   verset	Verset

   Extract the first element of the stream.

10. head :: HasCallStack => [a] -> a

    xmonad-contrib	XMonad.Config.Prime

    Extract the first element of a list, which must be non-empty. To disable the warning about partiality put {-# OPTIONS_GHC -Wno-x-partial -Wno-unrecognised-warning-flags #-} at the top of the file. To disable it throughout a package put the same options into ghc-options section of Cabal file. To disable it in GHCi put :set -Wno-x-partial -Wno-unrecognised-warning-flags into ~/.ghci config file. See also the migration guide.

    Examples

    >>> head [1, 2, 3]
    1
    

    >>> head [1..]
    1
    

    >>> head []
    *** Exception: Prelude.head: empty list
    

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