impl<T: Copy> Bound<&T> {
    /// Map a `Bound<&T>` to a `Bound<T>` by copying the contents of the bound.
    ///
    /// # Examples
    ///
    /// ```
    /// use std::ops::Bound::*;
    /// use std::ops::RangeBounds;
    ///
    /// assert_eq!((1..12).start_bound(), Included(&1));
    /// assert_eq!((1..12).start_bound().copied(), Included(1));
    /// ```
    #[must_use = "`self` will be dropped if the result is not used"]
    #[unstable(feature = "bound_copied", issue = ???)]
    pub fn copied(self) -> Bound<T> {
        match self {
            Bound::Unbounded => Bound::Unbounded,
            Bound::Included(x) => Bound::Included(*x),
            Bound::Excluded(x) => Bound::Excluded(*x),
        }
    }
}