+
+-- |> show3 5
+-- > ==> "005"
+show3 ∷ Integral n ⇒ n → AsciiBuilder
+{-# INLINEABLE show3 #-}
+show3 = A.unsafeFromBuilder ∘ go
+ where
+ go i | i ≥ 0 ∧ i < 10 = B.fromByteString "00" ⊕ BT.digit i
+ | i ≥ 0 ∧ i < 100 = B.fromByteString "0" ⊕ BT.integral i
+ | i ≥ 0 ∧ i < 1000 = BT.integral i
+ | otherwise = error ("show3: the integer i must satisfy 0 <= i < 1000: " ⧺ show i)