Implement requested changes from #146 review

Changelog.md

@@ -1,3 +1,8 @@
+[0.11.0.0] —
+ * [Add `indexMaybe` and synonym `(!?)` for indexing that returns `Maybe`](https://github.com/haskell/bytestring/pull/261)
+
+[0.11.0.0]: https://github.com/haskell/bytestring/compare/0.10.12.0...0.11.0.0
+
 [0.10.12.0] – August 2020
 
  * **Note:** There are several breaking changes planned to be included in v0.11.
@@ -9,7 +14,6 @@
  * [Add `IsList` instances for strict and lazy `ByteString` and for `ShortByteString`](https://github.com/haskell/bytestring/pull/219)
  * [Add `createUpToN'` and `unsafeCreateUpToN'` to `Data.ByteString.Internal`](https://github.com/haskell/bytestring/pull/245)
  * [Add `boundedPrim` to `Data.ByteString.Builder.Prim.Internal` and deprecate `boudedPrim`](https://github.com/haskell/bytestring/pull/246)
- * Add `indexMaybe` and synonym `(!?)` for indexing that returns `Maybe`
  * [Deprecate the `Data.ByteString.Lazy.Builder` and `Data.ByteString.Lazy.Builder.{ASCII,Extras}` modules](https://github.com/haskell/bytestring/pull/250)
  * [Fix documented complexity of `Data.ByteString.Lazy.length`](https://github.com/haskell/bytestring/pull/255)
  * [Assorted documentation fixes](https://github.com/haskell/bytestring/pull/248)

Data/ByteString.hs

@@ -1103,7 +1103,7 @@ index ps n
 --
 -- > 0 <= n < length bs
 --
--- @since 0.10.10.1
+-- @since 0.11.0.0
 indexMaybe :: ByteString -> Int -> Maybe Word8
 indexMaybe ps n
     | n < 0          = Nothing
@@ -1115,7 +1115,7 @@ indexMaybe ps n
 --
 -- > 0 <= n < length bs
 --
--- @since 0.10.10.1
+-- @since 0.11.0.0
 (!?) :: ByteString -> Int -> Maybe Word8
 (!?) = indexMaybe
 {-# INLINE (!?) #-}

Data/ByteString/Char8.hs

@@ -650,16 +650,16 @@ index = (w2c .) . B.index
 --
 -- > 0 <= n < length bs
 --
--- @since 0.10.10.1
+-- @since 0.11.0.0
 indexMaybe :: ByteString -> Int -> Maybe Char
-indexMaybe = ((fmap w2c) .) . B.indexMaybe
+indexMaybe = (fmap w2c .) . B.indexMaybe
 {-# INLINE indexMaybe #-}
 
 -- | /O(1)/ 'ByteString' index, starting from 0, that returns 'Just' if:
 --
 -- > 0 <= n < length bs
 --
--- @since 0.10.10.1
+-- @since 0.11.0.0
 (!?) :: ByteString -> Int -> Maybe Char
 (!?) = indexMaybe
 {-# INLINE (!?) #-}

Data/ByteString/Lazy.hs

@@ -901,7 +901,7 @@ index cs0 i         = index' cs0 i
 --
 -- > 0 <= n < length bs
 --
--- @since 0.10.10.1
+-- @since 0.11.0.0
 indexMaybe :: ByteString -> Int64 -> Maybe Word8
 indexMaybe _ i | i < 0 = Nothing
 indexMaybe cs0 i       = index' cs0 i
@@ -915,7 +915,7 @@ indexMaybe cs0 i       = index' cs0 i
 --
 -- > 0 <= n < length bs
 --
--- @since 0.10.10.1
+-- @since 0.11.0.0
 (!?) :: ByteString -> Int64 -> Maybe Word8
 (!?) = indexMaybe
 {-# INLINE (!?) #-}

Data/ByteString/Lazy/Char8.hs

@@ -533,16 +533,16 @@ index = (w2c .) . L.index
 --
 -- > 0 <= n < length bs
 --
--- @since 0.10.10.1
+-- @since 0.11.0.0
 indexMaybe :: ByteString -> Int64 -> Maybe Char
-indexMaybe = ((fmap w2c) .) . L.indexMaybe
+indexMaybe = (fmap w2c .) . L.indexMaybe
 {-# INLINE indexMaybe #-}
 
 -- | /O(1)/ 'ByteString' index, starting from 0, that returns 'Just' if:
 --
 -- > 0 <= n < length bs
 --
--- @since 0.10.10.1
+-- @since 0.11.0.0
 (!?) :: ByteString -> Int64 -> Maybe Char
 (!?) = indexMaybe
 {-# INLINE (!?) #-}

Data/ByteString/Short/Internal.hs

@@ -220,7 +220,7 @@ index sbs i
 --
 -- > 0 <= n < length bs
 --
--- @since 0.10.10.1
+-- @since 0.11.0.0
 indexMaybe :: ShortByteString -> Int -> Maybe Word8
 indexMaybe sbs i
   | i >= 0 && i < length sbs = Just $ unsafeIndex sbs i
@@ -230,7 +230,7 @@ indexMaybe sbs i
 --
 -- > 0 <= n < length bs
 --
--- @since 0.10.10.1
+-- @since 0.11.0.0
 (!?) :: ShortByteString -> Int -> Maybe Word8
 (!?) = indexMaybe