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1. newtype () => First a

   base-compat-batteries	Data.Monoid.Compat

   Maybe monoid returning the leftmost non-Nothing value. First a is isomorphic to Alt Maybe a, but precedes it historically.

   >>> getFirst (First (Just "hello") <> First Nothing <> First (Just "world"))
   Just "hello"
   

   Beware that Data.Monoid.First is different from Data.Semigroup.First. The former returns the first non-Nothing, so Data.Monoid.First Nothing <> x = x. The latter simply returns the first value, thus Data.Semigroup.First Nothing <> x = Data.Semigroup.First Nothing.

2. First :: Maybe a -> First a

   base-compat-batteries	Data.Monoid.Compat

   No documentation available.

3. newtype () => First a

   base-compat-batteries	Data.Semigroup.Compat

   Beware that Data.Semigroup.First is different from Data.Monoid.First. The former simply returns the first value, so Data.Semigroup.First Nothing <> x = Data.Semigroup.First Nothing. The latter returns the first non-Nothing, thus Data.Monoid.First Nothing <> x = x.

4. First :: a -> First a

   base-compat-batteries	Data.Semigroup.Compat

   No documentation available.

5. newtype () => First a

   relude	Relude.Monoid

   Maybe monoid returning the leftmost non-Nothing value. First a is isomorphic to Alt Maybe a, but precedes it historically.

   >>> getFirst (First (Just "hello") <> First Nothing <> First (Just "world"))
   Just "hello"
   

   Beware that Data.Monoid.First is different from Data.Semigroup.First. The former returns the first non-Nothing, so Data.Monoid.First Nothing <> x = x. The latter simply returns the first value, thus Data.Semigroup.First Nothing <> x = Data.Semigroup.First Nothing.

6. First :: Maybe a -> First a

   relude	Relude.Monoid

   No documentation available.

7. data First

   first-class-families	Fcf.Class.Bifunctor

   Type-level first. Apply a function along the first parameter of a bifunctor.

   Example

   >>> :kind! Eval (First ((+) 1) '(3,"a"))
   Eval (First ((+) 1) '(3,"a")) :: (Natural, Symbol)
   = '(4, "a")
   

8. type family First a :: Symbol

   generic-random	Generic.Random.Internal.Generic

   No documentation available.

9. newtype () => First a

   optparse-generic	Options.Generic

   Maybe monoid returning the leftmost non-Nothing value. First a is isomorphic to Alt Maybe a, but precedes it historically.

   >>> getFirst (First (Just "hello") <> First Nothing <> First (Just "world"))
   Just "hello"
   

   Beware that Data.Monoid.First is different from Data.Semigroup.First. The former returns the first non-Nothing, so Data.Monoid.First Nothing <> x = x. The latter simply returns the first value, thus Data.Semigroup.First Nothing <> x = Data.Semigroup.First Nothing.

10. First :: Maybe a -> First a

    optparse-generic	Options.Generic

    No documentation available.

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