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1. head :: forall (m :: Type -> Type) a . Monad m => Fold m a (Maybe a)

   streamly-core	Streamly.Internal.Data.Fold

   Deprecated: Please use "one" instead

2. head :: Monad m => Stream m a -> m (Maybe a)

   streamly-core	Streamly.Internal.Data.Stream

   No documentation available.

3. head :: Monad m => StreamK m a -> m (Maybe a)

   streamly-core	Streamly.Internal.Data.StreamK

   No documentation available.

4. head :: (HasCallStack, Monad m) => Stream m a -> m a

   vector-stream	Data.Stream.Monadic

   First element of the Stream or error if empty

5. head :: NonEmpty a -> a

   Agda	Agda.Utils.List1

   Extract the first element of the stream.

6. head :: List2 a -> a

   Agda	Agda.Utils.List2

   Safe. O(1).

7. head :: BinList a -> a

   binary-list	Data.BinaryList

   O(log n). Get the first element of a binary list.

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

   dimensional	Numeric.Units.Dimensional.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
   

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

   distribution-opensuse	OpenSuse.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
   

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

    faktory	Faktory.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
    

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