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

   numeric-prelude	NumericPrelude

   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

   numeric-prelude	NumericPrelude.Base

   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

   numhask	NumHask.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 :: ListLike full item => full -> item

   ListLike	Data.ListLike

   Extracts the first element of a ListLike.

5. head :: ListLike full item => full -> item

   ListLike	Data.ListLike.Base

   Extracts the first element of a ListLike.

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

   basic-prelude	BasicPrelude

   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
   

7. head :: Infinite a -> a

   ghc-lib-parser	GHC.Data.List.Infinite

   No documentation available.

8. head :: ShortText -> Char

   ghc-lib-parser	GHC.Data.ShortText

   O(1) Returns the first UTF-8 codepoint in the ShortText. Depending on the string in question, this may or may not be the actual first character in the string due to Unicode non-printable characters.

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

   ghc-lib-parser	GHC.Prelude.Basic

   No documentation available.

10. head :: Monad m => ListT m a -> m (Maybe a)

    list-t	ListT

    Execute, getting the head. Returns nothing if it's empty.

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