Improve code example for Option::unwrap_or_default

Author: GuillaumeGomez

library/core/src/option.rs

@@ -834,20 +834,12 @@ impl<T> Option<T> {
     ///
     /// # Examples
     ///
-    /// Converts a string to an integer, turning poorly-formed strings
-    /// into 0 (the default value for integers). [`parse`] converts
-    /// a string to any other type that implements [`FromStr`], returning
-    /// [`None`] on error.
-    ///
     /// ```
-    /// let good_year_from_input = "1909";
-    /// let bad_year_from_input = "190blarg";
-    /// // Result::ok() converts a Result<T> to an Option<T>
-    /// let good_year = good_year_from_input.parse().ok().unwrap_or_default();
-    /// let bad_year = bad_year_from_input.parse().ok().unwrap_or_default();
+    /// let x: Option<u32> = None;
+    /// let y: Option<u32> = Some(12);
     ///
-    /// assert_eq!(1909, good_year);
-    /// assert_eq!(0, bad_year);
+    /// assert_eq!(x.unwrap_or_default(), 0);
+    /// assert_eq!(y.unwrap_or_default(), 12);
     /// ```
     ///
     /// [default value]: Default::default