diff --git a/src/libcollections/btree/map.rs b/src/libcollections/btree/map.rs index 8a6d26c26bf..f6d196d2f58 100644 --- a/src/libcollections/btree/map.rs +++ b/src/libcollections/btree/map.rs @@ -1026,6 +1026,24 @@ impl<'a, K: Ord, V> OccupiedEntry<'a, K, V> { impl BTreeMap { /// Gets an iterator over the entries of the map. + /// + /// # Example + /// + /// ``` + /// use std::collections::BTreeMap; + /// + /// let mut map = BTreeMap::new(); + /// map.insert(1u, "a"); + /// map.insert(2u, "b"); + /// map.insert(3u, "c"); + /// + /// for (key, value) in map.iter() { + /// println!("{}: {}", key, value); + /// } + /// + /// let (first_key, first_value) = map.iter().next().unwrap(); + /// assert_eq!((*first_key, *first_value), (1u, "a")); + /// ``` #[unstable = "matches collection reform specification, waiting for dust to settle"] pub fn iter<'a>(&'a self) -> Entries<'a, K, V> { let len = self.len();