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Within LTS Haskell 24.3 (ghc-9.10.2)

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1. head :: Monad m => Producer ByteString m () -> m (Maybe Word8)

   pipes-bytestring	Pipes.ByteString

   Retrieve the first Word8

2. head :: Foldable f => f a -> Maybe a

   protolude	Protolude.List

   No documentation available.

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

   protolude	Protolude.Partial

   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 :: NonEmptyF a b -> a

   recursion-schemes	Data.Functor.Base

   No documentation available.

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

   ghc-internal	GHC.Internal.Data.List

   Warning: This is a partial function, it throws an error on empty lists. Use pattern matching, uncons or listToMaybe instead. Consider refactoring to use Data.List.NonEmpty.

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

   ghc-internal	GHC.Internal.Data.OldList

   Warning: This is a partial function, it throws an error on empty lists. Use pattern matching, uncons or listToMaybe instead. Consider refactoring to use Data.List.NonEmpty.

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

   ghc-internal	GHC.Internal.List

   Warning: This is a partial function, it throws an error on empty lists. Use pattern matching, uncons or listToMaybe instead. Consider refactoring to use Data.List.NonEmpty.

8. head :: Infinite a -> a

   infinite-list	Data.List.Infinite

   Get the first elements of an infinite list.

9. head :: JSString -> Char

   jsaddle	Data.JSString

   O(1) Returns the first character of a JSString, which must be non-empty. Subject to fusion.

10. head :: HasCallStack => Stream Char -> Char

    jsaddle	Data.JSString.Internal.Fusion.Common

    O(1) Returns the first character of a Stream Char, which must be non-empty. This is a partial function, consider using uncons. Properties

    head . stream = head
    

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