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1. head :: List2 a -> a

   Agda	Agda.Utils.List2

   Safe. O(1).

2. head :: BinList a -> a

   binary-list	Data.BinaryList

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

3. head :: forall (n :: Natural) a . Vec (n + 1) a -> a

   clash-prelude	Clash.Explicit.Prelude

   Extract the first element of a vector

   >>> head (1:>2:>3:>Nil)
   1
   

   >>> head Nil
   <interactive>:...
   • Couldn't match type ‘1’ with ‘0’
   Expected: Vec (0 + 1) a
   Actual: Vec 0 a
   • In the first argument of ‘head’, namely ‘Nil’
   In the expression: head Nil
   In an equation for ‘it’: it = head Nil
   

   # 445 "srcClashSized/Vector.hs"

4. head :: forall (n :: Natural) a . Vec (n + 1) a -> a

   clash-prelude	Clash.Explicit.Prelude.Safe

   Extract the first element of a vector

   >>> head (1:>2:>3:>Nil)
   1
   

   >>> head Nil
   <interactive>:...
   • Couldn't match type ‘1’ with ‘0’
   Expected: Vec (0 + 1) a
   Actual: Vec 0 a
   • In the first argument of ‘head’, namely ‘Nil’
   In the expression: head Nil
   In an equation for ‘it’: it = head Nil
   

   # 445 "srcClashSized/Vector.hs"

5. head :: forall (n :: Natural) a . Vec (n + 1) a -> a

   clash-prelude	Clash.Prelude

   Extract the first element of a vector

   >>> head (1:>2:>3:>Nil)
   1
   

   >>> head Nil
   <interactive>:...
   • Couldn't match type ‘1’ with ‘0’
   Expected: Vec (0 + 1) a
   Actual: Vec 0 a
   • In the first argument of ‘head’, namely ‘Nil’
   In the expression: head Nil
   In an equation for ‘it’: it = head Nil
   

   # 445 "srcClashSized/Vector.hs"

6. head :: forall (n :: Natural) a . Vec (n + 1) a -> a

   clash-prelude	Clash.Prelude.Safe

   Extract the first element of a vector

   >>> head (1:>2:>3:>Nil)
   1
   

   >>> head Nil
   <interactive>:...
   • Couldn't match type ‘1’ with ‘0’
   Expected: Vec (0 + 1) a
   Actual: Vec 0 a
   • In the first argument of ‘head’, namely ‘Nil’
   In the expression: head Nil
   In an equation for ‘it’: it = head Nil
   

   # 445 "srcClashSized/Vector.hs"

7. head :: forall (n :: Natural) a . Vec (n + 1) a -> a

   clash-prelude	Clash.Sized.Vector

   Extract the first element of a vector

   >>> head (1:>2:>3:>Nil)
   1
   

   >>> head Nil
   <interactive>:...
   • Couldn't match type ‘1’ with ‘0’
   Expected: Vec (0 + 1) a
   Actual: Vec 0 a
   • In the first argument of ‘head’, namely ‘Nil’
   In the expression: head Nil
   In an equation for ‘it’: it = head Nil
   

   # 445 "srcClashSized/Vector.hs"

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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