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1. head :: [a] -> Maybe a

   incipit-base	Incipit.List

   Return Just the head of a list.

2. head :: AList a -> a

   monad-par-extras	Control.Monad.Par.AList

   O(n) take the head element of an AList NB. linear-time, because the list might look like this:

   (((... `append` a) `append` b) `append` c)
   

3. head :: SymVal a => SList a -> SBV a

   sbv	Data.SBV.List

   head returns the first element of a list. Unspecified if the list is empty.

   >>> prove $ \c -> head (singleton c) .== (c :: SInteger)
   Q.E.D.
   

4. head :: SString -> SChar

   sbv	Data.SBV.String

   head returns the head of a string. Unspecified if the string is empty.

   >>> prove $ \c -> head (singleton c) .== c
   Q.E.D.
   

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

   streamly-core	Streamly.Data.Fold

   Deprecated: Please use "one" instead

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

   streamly-core	Streamly.Internal.Data.Fold

   Deprecated: Please use "one" instead

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

   streamly-core	Streamly.Internal.Data.Stream

   No documentation available.

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

   streamly-core	Streamly.Internal.Data.StreamK

   No documentation available.

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

   vector-stream	Data.Stream.Monadic

   First element of the Stream or error if empty

10. head :: NonEmpty a -> a

    Agda	Agda.Utils.List1

    Extract the first element of the stream.

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