Method try_leaf_insert

cranelift/bforest/src/node.rs:193–217

Try to insert `key, value` at `index` in a leaf node, but fail and return false if the node is full.

(&mut self, index: usize, key: F::Key, value: F::Value)

    /// Try to insert `key, value` at `index` in a leaf node, but fail and return false if the node
    /// is full.
    pub fn try_leaf_insert(&mut self, index: usize, key: F::Key, value: F::Value) -> bool {
        match *self {
            Self::Leaf {
                ref mut size,
                ref mut keys,
                ref mut vals,
            } => {
                let sz = usize::from(*size);
                let keys = keys.borrow_mut();
                let vals = vals.borrow_mut();
                debug_assert!(sz <= keys.len());
                debug_assert!(index <= sz);

                if let Some(ks) = keys.get_mut(0..=sz) {
                    *size = (sz + 1) as u8;
                    slice_insert(ks, index, key);
                    slice_insert(&mut vals[0..=sz], index, value);
                    true
                } else {
                    false
                }
            }
            _ => panic!("Expected leaf node"),
        }
    }

    /// Split off the second half of this node.
    /// It is assumed that this a completely full inner or leaf node.