fn insert(&mut self, key: usize, value: E) -> Option<E> {
        self.check_null("insert");
        if self.data.get_label().counter() == 1 {
            self.data.insert(key, value)
        } else {
            None
        }
    }
/// Insert an element into this array. Returns `None` if:
///
/// - The array is referenced by another pointer
/// - The index given is out-of-bounds
/// - There was nothing in the slot previously
Insert an element into this array. Returns `None` if:
The array is referenced by another pointer
The index given is out-of-bounds
There was nothing in the slot previously
Insert an element into this array . Returns ` None ` if : The array is referenced by another pointer The index given is out - of - bounds There was nothing in the slot previously
fn insert(&mut self, key: usize, value: E) -> Option<E> {
        self.check_null("insert");
        if self.data.get_label().counter() == 1 {
            self.data.insert(key, value)
        } else {
            None
        }
    }
fn insert ( & mut self , key : usize , value : E ) -> Option < E > { self . check_null ( " " ) ; if self . data . get_label ( ) . counter ( ) == 1 { self . data . insert ( key , value ) } else { None } }
Insert an element into this array.
Insert an element into this array .
&mut self
key
usize
value
E