message: Add doc example for `num_traits::Num::from_str_radix`.
diff: @@ -43,6 +43,18 @@ pub trait Num: PartialEq + Zero + One
  type FromStrRadixErr;
  /// Convert from a string and radix <= 36.
  + ///
  + /// # Examples
  + ///
  + /// ```rust
  + /// use num_traits::Num;
  + ///
  + /// let result = <i32 as Num>::from_str_radix("27", 10);
  + /// assert_eq!(result, Ok(27));
  + ///
  + /// let result = <i32 as Num>::from_str_radix("foo", 10);
  + /// assert!(result.is_err());
  + /// ```
  fn from_str_radix(str: &str, radix: u32) -> Result<Self, Self::FromStrRadixErr>;
  }
  