Add buniq to README

It's another perfectly legitimate way to construct an object!

README.md

@@ -52,7 +52,9 @@ example data types:
 {-# LANGUAGE TypeApplications #-}
 module Main where
 
+import Control.Applicative (Alternative (empty))
 import Control.Lens ((.~), (^.), (&), Const (..), Identity, anyOf)
+import Data.Barbie (ProductB (buniq))
 import Data.Functor.Const (Const (..))
 import Data.Functor.Identity (Identity (..))
 import Data.Generic.HKD
@@ -178,14 +180,24 @@ eg7 = eg6 [1] [] ["Tom", "Tim"]
 -- Triple [1] [] ["Tom","Tim"]
 ```
 
+If you're _still_ not satisfied, check out the
+[`buniq`](https://hackage.haskell.org/package/barbies-1.1.2.1/docs/Data-Barbie.html#v:buniq)
+method hiding in `barbies`:
+
+```haskell
+eg8 :: HKD Triple []
+eg8 = buniq empty
+-- Triple [] [] []
+```
+
 ### Field Access
 
 The `field` lens, when given a type-applied field name, allows us to focus on
 fields within a record:
 
 ```haskell
-eg8 :: Last Int
+eg9 :: Last Int
-eg8 = eg0 ^. field @"age"
+eg9 = eg0 ^. field @"age"
 -- Last {getLast = Nothing}
 ```
 
@@ -194,9 +206,9 @@ record (note that these set values will _also_ need to be in our functor of
 choice):
 
 ```haskell
-eg9 :: Partial User
+eg10 :: Partial User
-eg9 = eg0 & field @"name"      .~ pure "Evil Tom"
+eg10 = eg0 & field @"name"      .~ pure "Evil Tom"
-          & field @"likesDogs" .~ pure False
+           & field @"likesDogs" .~ pure False
 -- User
 --   { name      = Last {getLast = Just "Evil Tom"}
 --   , age       = Last {getLast = Nothing}
@@ -208,8 +220,8 @@ This also means, for example, we can check whether a particular value has been
 completed for a given partial type:
 
 ```haskell
-eg10 :: Bool
+eg11 :: Bool
-eg10 = anyOf (field @"name") (isJust . getLast) eg0
+eg11 = anyOf (field @"name") (isJust . getLast) eg0
 -- False
 ```
 
@@ -218,8 +230,8 @@ Finally, thanks to the fact that this library exploits some of the internals of
 doesn't exist in our type:
 
 ```{haskell, ignore}
-eg11 :: Identity ()
+eg12 :: Identity ()
-eg11 = eg3 ^. field @"oops"
+eg12 = eg3 ^. field @"oops"
 -- error:
 -- • The type User does not contain a field named 'oops'.
 ```
@@ -230,8 +242,8 @@ Just as with field names, we can use positions when working with non-record
 product types:
 
 ```haskell
-eg12 :: Labels Triple
+eg13 :: Labels Triple
-eg12 = mempty & position @1 .~ Const "hello"
+eg13 = mempty & position @1 .~ Const "hello"
               & position @2 .~ Const "world"
 -- Triple
 --   Const "hello"
@@ -242,8 +254,8 @@ eg12 = mempty & position @1 .~ Const "hello"
 Again, this is a `Lens`, so we can just as easily _set_ values:
 
 ```haskell
-eg13 :: Partial User
+eg14 :: Partial User
-eg13 = eg9 & position @2 .~ pure 25
+eg14 = eg10 & position @2 .~ pure 25
 -- User
 --   { name      = Last {getLast = Just "Evil Tom"}
 --   , age       = Last {getLast = Just 25}
@@ -255,8 +267,8 @@ Similarly, the internals here come to us courtesy of `generic-lens`, so the
 type errors are a delight:
 
 ```{haskell, ignore}
-eg14 :: Identity ()
+eg15 :: Identity ()
-eg14 = deconstruct @Identity triple ^. position @4
+eg15 = deconstruct @Identity triple ^. position @4
 -- error:
 -- • The type Triple does not contain a field at position 4
 ```
@@ -268,8 +280,8 @@ names of the fields into the functor we're using. The `label` value gives us
 this interface:
 
 ```haskell
-eg15 :: Labels User
+eg16 :: Labels User
-eg15 = label
+eg16 = label
 -- User
 --   { name = Const "name"
 --   , age = Const "age"
@@ -284,8 +296,8 @@ can implement functions such as `labelsWhere`, which returns the names of all
 fields whose values satisfy some predicate:
 
 ```haskell
-eg16 :: [String]
+eg17 :: [String]
-eg16 = labelsWhere (isNothing . getLast) eg9
+eg17 = labelsWhere (isNothing . getLast) eg10
 -- ["age"]
 ```