diff options
| -rw-r--r-- | library/core/src/cell.rs | 15 | ||||
| -rw-r--r-- | library/coretests/tests/cell.rs | 4 |
2 files changed, 6 insertions, 13 deletions
diff --git a/library/core/src/cell.rs b/library/core/src/cell.rs index e789601a409..09117e4968d 100644 --- a/library/core/src/cell.rs +++ b/library/core/src/cell.rs @@ -544,7 +544,7 @@ impl<T: Copy> Cell<T> { unsafe { *self.value.get() } } - /// Updates the contained value using a function and returns the new value. + /// Updates the contained value using a function. /// /// # Examples /// @@ -554,21 +554,14 @@ impl<T: Copy> Cell<T> { /// use std::cell::Cell; /// /// let c = Cell::new(5); - /// let new = c.update(|x| x + 1); - /// - /// assert_eq!(new, 6); + /// c.update(|x| x + 1); /// assert_eq!(c.get(), 6); /// ``` #[inline] #[unstable(feature = "cell_update", issue = "50186")] - pub fn update<F>(&self, f: F) -> T - where - F: FnOnce(T) -> T, - { + pub fn update(&self, f: impl FnOnce(T) -> T) { let old = self.get(); - let new = f(old); - self.set(new); - new + self.set(f(old)); } } diff --git a/library/coretests/tests/cell.rs b/library/coretests/tests/cell.rs index d6a401c2b4d..781a46c3744 100644 --- a/library/coretests/tests/cell.rs +++ b/library/coretests/tests/cell.rs @@ -50,10 +50,10 @@ fn smoketest_cell() { fn cell_update() { let x = Cell::new(10); - assert_eq!(x.update(|x| x + 5), 15); + x.update(|x| x + 5); assert_eq!(x.get(), 15); - assert_eq!(x.update(|x| x / 3), 5); + x.update(|x| x / 3); assert_eq!(x.get(), 5); } |