(incomplete) b+tree.ts

// Type parameters can have default values,
// so `var t: BTree` means `var t: BTree<any,any>`
export class BTree<K=any, V=any>
{
  // Root node (key-value pairs are stored in here)
  private _root: BNode<K, V>;
  // Total number of items in the collection
  _size: number = 0;
  // Maximum number of items in a single node
  _maxNodeSize: number;
  // This function must return less-than-0 if a<b and above-zero if a>b
  _compare: (a:K, b:K) => number;
    
  public constructor(entries?: [K,V][], 
                     compare?: (a: K, b: K) => number, 
                     maxNodeSize?: number) { ... }
  
  get size() { return this._size; }
  clear() { ... }
  get(key: K): V | undefined { ... }
  set(key: K, value: V, overwrite?: boolean): boolean { ... }
  has(key: K): boolean { ... }
  delete(key: K) { ... }
  /** Quickly clones the tree by marking the root node as shared. 
   *  Both copies remain editable. When you modify either copy, any
   *  nodes that are shared (or potentially shared) between the two
   *  copies are cloned so that the changes do not affect other copies.
   *  This is known as copy-on-write behavior, or "lazy copying". */
  clone(): BTree<K,V> { ... }
  ...
}