Skip to content
Merged
Changes from all commits
Commits
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
64 changes: 35 additions & 29 deletions library/core/src/option.rs
Original file line number Diff line number Diff line change
Expand Up @@ -594,34 +594,6 @@ impl<T> Option<T> {
}
}

/// Inserts `value` into the option then returns a mutable reference to it.
///
/// If the option already contains a value, the old value is dropped.
///
/// # Example
///
/// ```
/// let mut opt = None;
/// let val = opt.insert(1);
/// assert_eq!(*val, 1);
/// assert_eq!(opt.unwrap(), 1);
/// let val = opt.insert(2);
/// assert_eq!(*val, 2);
/// *val = 3;
/// assert_eq!(opt.unwrap(), 3);
/// ```
#[inline]
#[stable(feature = "option_insert", since = "1.53.0")]
pub fn insert(&mut self, value: T) -> &mut T {
*self = Some(value);

match self {
Some(v) => v,
// SAFETY: the code above just filled the option
None => unsafe { hint::unreachable_unchecked() },
}
}

/////////////////////////////////////////////////////////////////////////
// Iterator constructors
/////////////////////////////////////////////////////////////////////////
Expand Down Expand Up @@ -849,12 +821,46 @@ impl<T> Option<T> {
}

/////////////////////////////////////////////////////////////////////////
// Entry-like operations to insert if None and return a reference
// Entry-like operations to insert a value and return a reference
/////////////////////////////////////////////////////////////////////////

/// Inserts `value` into the option then returns a mutable reference to it.
///
/// If the option already contains a value, the old value is dropped.
///
/// See also [`Option::get_or_insert`], which doesn't update the value if
/// the option already contains [`Some`].
///
/// # Example
///
/// ```
/// let mut opt = None;
/// let val = opt.insert(1);
/// assert_eq!(*val, 1);
/// assert_eq!(opt.unwrap(), 1);
/// let val = opt.insert(2);
/// assert_eq!(*val, 2);
/// *val = 3;
/// assert_eq!(opt.unwrap(), 3);
/// ```
#[inline]
#[stable(feature = "option_insert", since = "1.53.0")]
pub fn insert(&mut self, value: T) -> &mut T {
*self = Some(value);

match self {
Some(v) => v,
// SAFETY: the code above just filled the option
None => unsafe { hint::unreachable_unchecked() },
}
}

/// Inserts `value` into the option if it is [`None`], then
/// returns a mutable reference to the contained value.
///
/// See also [`Option::insert`], which updates the value even if
/// the option already contains [`Some`].
///
/// # Examples
///
/// ```
Expand Down