diff --git a/library/core/src/array/mod.rs b/library/core/src/array/mod.rs index 16baef137cb..01bf9d5ef1e 100644 --- a/library/core/src/array/mod.rs +++ b/library/core/src/array/mod.rs @@ -368,16 +368,23 @@ macro_rules! array_impl_default { #[cfg(not(bootstrap))] #[lang = "array"] impl [T; N] { - /// Returns an array of the same size as self, with `f` applied to each element. + /// Returns an array of the same size as `self`, with function `f` applied to each element. + /// The closure will be called on elements 0 up to but excluding N. /// /// # Examples + /// /// ``` /// # #![feature(array_map)] /// let x = [1, 2, 3]; /// let y = x.map(|v| v + 1); /// assert_eq!(y, [2, 3, 4]); + /// + /// let x = [1, 2, 3]; + /// let mut temp = 0; + /// let y = x.map(|v| { temp += 1; v * temp }); + /// assert_eq!(y, [1, 4, 9]); /// ``` - #[unstable(feature = "array_map", issue = "77777")] + #[unstable(feature = "array_map", issue = "75243")] pub fn map(self, mut f: F) -> [U; N] where F: FnMut(T) -> U,