diff options
| -rw-r--r-- | library/core/src/iter/traits/iterator.rs | 26 |
1 files changed, 8 insertions, 18 deletions
diff --git a/library/core/src/iter/traits/iterator.rs b/library/core/src/iter/traits/iterator.rs index 46ef12cd938..b5aa7257cf3 100644 --- a/library/core/src/iter/traits/iterator.rs +++ b/library/core/src/iter/traits/iterator.rs @@ -648,11 +648,9 @@ pub trait Iterator { /// Creates an iterator which uses a closure to determine if an element /// should be yielded. /// - /// The closure must return `true` or `false`. `filter()` creates an - /// iterator which calls this closure on each element. If the closure - /// returns `true`, then the element is returned. If the closure returns - /// `false`, it will try again, and call the closure on the next element, - /// seeing if it passes the test. + /// Given an element the closure must return `true` or `false`. The returned + /// iterator will yield only the elements for which the closure returns + /// true. /// /// # Examples /// @@ -719,24 +717,16 @@ pub trait Iterator { /// Creates an iterator that both filters and maps. /// - /// The closure must return an [`Option<T>`]. `filter_map` creates an - /// iterator which calls this closure on each element. If the closure - /// returns [`Some(element)`][`Some`], then that element is returned. If the - /// closure returns [`None`], it will try again, and call the closure on the - /// next element, seeing if it will return [`Some`]. + /// The returned iterator yields only the `value`s for which the supplied + /// closure returns `Some(value)`. /// - /// Why `filter_map` and not just [`filter`] and [`map`]? The key is in this - /// part: + /// `filter_map` can be used to make chains of [`filter`] and [`map`] more + /// concise. The example below shows how a `map().filter().map()` can be + /// shortened to a single call to `filter_map`. /// /// [`filter`]: Iterator::filter /// [`map`]: Iterator::map /// - /// > If the closure returns [`Some(element)`][`Some`], then that element is returned. - /// - /// In other words, it removes the [`Option<T>`] layer automatically. If your - /// mapping is already returning an [`Option<T>`] and you want to skip over - /// [`None`]s, then `filter_map` is much, much nicer to use. - /// /// # Examples /// /// Basic usage: |