diff options
Diffstat (limited to 'src/liballoc')
| -rw-r--r-- | src/liballoc/collections/btree/map.rs | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/src/liballoc/collections/btree/map.rs b/src/liballoc/collections/btree/map.rs index e70f881bc3d..4dc004864fd 100644 --- a/src/liballoc/collections/btree/map.rs +++ b/src/liballoc/collections/btree/map.rs @@ -810,9 +810,38 @@ impl<K: Ord, V> BTreeMap<K, V> { K: Borrow<Q>, Q: Ord, { + self.remove_entry(key).map(|(_, v)| v) + } + + /// Removes a key from the map, returning the stored key and value if the key + /// was previously in the map. + /// + /// The key may be any borrowed form of the map's key type, but the ordering + /// on the borrowed form *must* match the ordering on the key type. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ``` + /// #![feature(btreemap_remove_entry)] + /// use std::collections::BTreeMap; + /// + /// let mut map = BTreeMap::new(); + /// map.insert(1, "a"); + /// assert_eq!(map.remove_entry(&1), Some((1, "a"))); + /// assert_eq!(map.remove_entry(&1), None); + /// ``` + #[unstable(feature = "btreemap_remove_entry", issue = "66714")] + pub fn remove_entry<Q: ?Sized>(&mut self, key: &Q) -> Option<(K, V)> + where + K: Borrow<Q>, + Q: Ord, + { match search::search_tree(self.root.as_mut(), key) { Found(handle) => Some( - OccupiedEntry { handle, length: &mut self.length, _marker: PhantomData }.remove(), + OccupiedEntry { handle, length: &mut self.length, _marker: PhantomData } + .remove_entry(), ), GoDown(_) => None, } |
