io: add missing Option to doc
@@ -173,10 +173,11 @@ cfg_io_util! {
/// [`BufRead::split`](std::io::BufRead::split).
///
/// The stream returned from this function will yield instances of
- /// [`io::Result`]`<`[`Vec<u8>`]`>`. Each vector returned will *not* have
+ /// [`io::Result`]`<`[`Option`]`<`[`Vec<u8>`]`>>`. Each vector returned will *not* have
/// the delimiter byte at the end.
///
/// [`io::Result`]: std::io::Result
+ /// [`Option`]: core::option::Option
/// [`Vec<u8>`]: std::vec::Vec
///
/// # Errors
@@ -210,10 +211,11 @@ cfg_io_util! {
/// This method is the async equivalent to [`BufRead::lines`](std::io::BufRead::lines).
///
/// The stream returned from this function will yield instances of
- /// [`io::Result`]`<`[`String`]`>`. Each string returned will *not* have a newline
+ /// [`io::Result`]`<`[`Option`]`<`[`String`]`>>`. Each string returned will *not* have a newline
/// byte (the 0xA byte) or CRLF (0xD, 0xA bytes) at the end.
///
/// [`io::Result`]: std::io::Result
+ /// [`Option`]: core::option::Option
/// [`String`]: String
///
/// # Errors
