pub fn insert(&mut self, key: K, value: V) -> Option<V> {
        let opt_old_value = BurstTrieNode::insert(self.root, key, value, 0, &mut self.root);
        if opt_old_value.is_none() {
            self.len += 1;
        }
        opt_old_value
    }
/// Inserts a key-value pair from the map. If the key already had a value
/// present in the map, that value is returned. Otherwise, `None` is returned.
///
/// # Examples
///
/// ```rust
/// use burst_trie::BurstTrieMap;
///
/// let mut a = BurstTrieMap::new();
/// assert_eq!(a.len(), 0);
/// a.insert("a", 0u32);
/// assert_eq!(a.len(), 1);
/// assert_eq!(a.insert("a", 1), Some(0));
/// assert_eq!(a.len(), 1);
/// ```
Inserts a key-value pair from the map. If the key already had a value
present in the map, that value is returned. Otherwise, `None` is returned.
Inserts a key - value pair from the map . If the key already had a value present in the map that value is returned . Otherwise ` None ` is returned .
pub fn insert(&mut self, key: K, value: V) -> Option<V> {
        let opt_old_value = BurstTrieNode::insert(self.root, key, value, 0, &mut self.root);
        if opt_old_value.is_none() {
            self.len += 1;
        }
        opt_old_value
    }
pub fn insert ( & mut self , key : K , value : V ) -> Option < V > { let opt_old_value = BurstTrieNode :: insert ( self . root , key , value , 0 , & mut self . root ) ; if opt_old_value . is_none ( ) { self . len += 1 ; } opt_old_value }
Inserts a key-value pair from the map.
Inserts a key - value pair from the map .
&mut self
key
K
value
V
&mut self
key
K
value
V
examples
```rust
use burst_trie::BurstTrieMap.


` ` ` rust use burst_trie :: BurstTrieMap .