diff --git a/library/core/src/option.rs b/library/core/src/option.rs
index e8850176f7cd3..611f4ab38ab33 100644
--- a/library/core/src/option.rs
+++ b/library/core/src/option.rs
@@ -556,14 +556,16 @@ impl<T> Option<T> {
     /// # Examples
     ///
     /// ```
+    /// #![feature(is_some_with)]
+    ///
     /// let x: Option<u32> = Some(2);
-    /// assert_eq!(x.is_some_with(|x| x > 1), true);
+    /// assert_eq!(x.is_some_with(|&x| x > 1), true);
     ///
     /// let x: Option<u32> = Some(0);
-    /// assert_eq!(x.is_some_with(|x| x > 1), false);
+    /// assert_eq!(x.is_some_with(|&x| x > 1), false);
     ///
     /// let x: Option<u32> = None;
-    /// assert_eq!(x.is_some_with(|x| x > 1), false);
+    /// assert_eq!(x.is_some_with(|&x| x > 1), false);
     /// ```
     #[must_use]
     #[inline]
diff --git a/library/core/src/result.rs b/library/core/src/result.rs
index 9991112e7f553..fbd6d419236ae 100644
--- a/library/core/src/result.rs
+++ b/library/core/src/result.rs
@@ -547,14 +547,16 @@ impl<T, E> Result<T, E> {
     /// # Examples
     ///
     /// ```
+    /// #![feature(is_some_with)]
+    ///
     /// let x: Result<u32, &str> = Ok(2);
-    /// assert_eq!(x.is_ok_with(|x| x > 1), true);
+    /// assert_eq!(x.is_ok_with(|&x| x > 1), true);
     ///
     /// let x: Result<u32, &str> = Ok(0);
-    /// assert_eq!(x.is_ok_with(|x| x > 1), false);
+    /// assert_eq!(x.is_ok_with(|&x| x > 1), false);
     ///
     /// let x: Result<u32, &str> = Err("hey");
-    /// assert_eq!(x.is_ok_with(|x| x > 1), false);
+    /// assert_eq!(x.is_ok_with(|&x| x > 1), false);
     /// ```
     #[must_use]
     #[inline]
@@ -589,16 +591,17 @@ impl<T, E> Result<T, E> {
     /// # Examples
     ///
     /// ```
+    /// #![feature(is_some_with)]
     /// use std::io::{Error, ErrorKind};
     ///
     /// let x: Result<u32, Error> = Err(Error::new(ErrorKind::NotFound, "!"));
     /// assert_eq!(x.is_err_with(|x| x.kind() == ErrorKind::NotFound), true);
     ///
     /// let x: Result<u32, Error> = Err(Error::new(ErrorKind::PermissionDenied, "!"));
-    /// assert_eq!(x.is_ok_with(|x| x.kind() == ErrorKind::NotFound), false);
+    /// assert_eq!(x.is_err_with(|x| x.kind() == ErrorKind::NotFound), false);
     ///
     /// let x: Result<u32, Error> = Ok(123);
-    /// assert_eq!(x.is_ok_with(|x| x.kind() == ErrorKind::NotFound), false);
+    /// assert_eq!(x.is_err_with(|x| x.kind() == ErrorKind::NotFound), false);
     /// ```
     #[must_use]
     #[inline]