Skip to content

Implement Option::replace in the core library #52003

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 3 commits into from
Jul 13, 2018
Merged

Implement Option::replace in the core library #52003

Changes from 1 commit
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
6035534
Implement `Option::replace` in the core library
Kerollmops Jul 4, 2018
af87a35
Add a basic test to `Option::replace`
Jul 9, 2018
c8f0e6f
Fix the documentation of `Option::replace`
Jul 9, 2018
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
27 changes: 27 additions & 0 deletions src/libcore/option.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -845,6 +845,33 @@ impl<T> Option<T> {
pub fn take(&mut self) -> Option<T> {
mem::replace(self, None)
}

/// Replaces the actual value in the option by the value given in parameter,
/// returning the old value if present,
/// leaving a `Some` in its place without deinitializing either one.
Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Ooops.. And I forgot to add [] around Some.

///
/// [`Some`]: #variant.Some
///
/// # Examples
///
/// ```
/// #![feature(option_replace)]
///
/// let mut x = Some(2);
/// let old = x.replace(5);
/// assert_eq!(x, Some(5));
/// assert_eq!(old, Some(2));
///
/// let mut x = None;
/// let old = x.replace(3);
/// assert_eq!(x, Some(3));
/// assert_eq!(old, None);
/// ```
#[inline]
#[unstable(feature = "option_replace", issue = "51998")]
pub fn replace(&mut self, value: T) -> Option<T> {
mem::replace(self, Some(value))
}
}

impl<'a, T: Clone> Option<&'a T> {
Expand Down