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Add unstable Option::copied()

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This commit is contained in:
Konrad Borowski 2018-12-05 14:39:36 +01:00
parent 21cb46a6e9
commit 705383adb0
1 changed files with 42 additions and 0 deletions
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42
src/libcore/option.rs
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@ -884,6 +884,48 @@ impl<T> Option<T> {
}
}
impl<'a, T: Copy> Option<&'a T> {
/// Maps an `Option<&T>` to an `Option<T>` by copying the contents of the
/// option.
///
/// # Examples
///
/// ```
/// #![feature(copied)]
///
/// let x = 12;
/// let opt_x = Some(&x);
/// assert_eq!(opt_x, Some(&12));
/// let copied = opt_x.copied();
/// assert_eq!(copied, Some(12));
/// ```
#[unstable(feature = "copied", issue = "0")]
pub fn copied(self) -> Option<T> {
self.map(|&t| t)
}
}
impl<'a, T: Copy> Option<&'a mut T> {
/// Maps an `Option<&mut T>` to an `Option<T>` by copying the contents of the
/// option.
///
/// # Examples
///
/// ```
/// #![feature(copied)]
///
/// let mut x = 12;
/// let opt_x = Some(&mut x);
/// assert_eq!(opt_x, Some(&mut 12));
/// let copied = opt_x.copied();
/// assert_eq!(copied, Some(12));
/// ```
#[unstable(feature = "copied", issue = "0")]
pub fn copied(self) -> Option<T> {
self.map(|&mut t| t)
}
}
impl<'a, T: Clone> Option<&'a T> {
/// Maps an `Option<&T>` to an `Option<T>` by cloning the contents of the
/// option.