BREAKING(data_structures): docs & private internals

This commit completes documentation for the
data_structures module, and makes the internals of
`BinarySearchTree` properly private, so that
`BinarySearchNode` is not leaked.

_tools/check_docs.ts

@@ -24,6 +24,7 @@ const ENTRY_POINTS = [
   "../collections/mod.ts",
   "../internal/mod.ts",
   "../media_types/mod.ts",
+  "../data_structures/mod.ts",
 ] as const;
 
 const MD_SNIPPET = /(?<=```ts\n)(\n|.)*(?=\n```)/g;

data_structures/_binary_search_tree_private.ts

@@ -0,0 +1,39 @@
+import type { BinarySearchNode } from "./_binary_search_node.ts";
+import type { Direction } from "./_red_black_node.ts";
+import type { BinarySearchTree } from "./binary_search_tree.ts";
+
+// These are the private methods and properties that are shared between the
+// binary search tree and red-black tree implementations. They are not meant
+// to be used outside of the data structures module.
+export const internals: {
+  /** Returns the root node of the binary search tree. */
+  getRoot<T>(tree: BinarySearchTree<T>): BinarySearchNode<T> | null;
+  /** Sets the root node of the binary search tree. */
+  setRoot<T>(
+    tree: BinarySearchTree<T>,
+    node: BinarySearchNode<T> | null,
+  ): void;
+  getCompare<T>(tree: BinarySearchTree<T>): (a: T, b: T) => number;
+  setCompare<T>(
+    tree: BinarySearchTree<T>,
+    compare: (a: T, b: T) => number,
+  ): void;
+  findNode<T>(
+    tree: BinarySearchTree<T>,
+    value: T,
+  ): BinarySearchNode<T> | null;
+  rotateNode<T>(
+    tree: BinarySearchTree<T>,
+    node: BinarySearchNode<T>,
+    direction: Direction,
+  ): void;
+  insertNode<T>(
+    tree: BinarySearchTree<T>,
+    Node: typeof BinarySearchNode,
+    value: T,
+  ): BinarySearchNode<T> | null;
+  removeNode<T>(
+    tree: BinarySearchTree<T>,
+    node: BinarySearchNode<T>,
+  ): BinarySearchNode<T> | null;
+} = {} as typeof internals;

data_structures/binary_heap.ts

@@ -56,25 +56,120 @@ function getParentIndex(index: number) {
  * assertEquals([...words], ["truck", "tank", "car"]);
  * assertEquals([...words], []);
  * ```
+ *
+ * @typeparam T The type of the values stored in the binary heap.
  */
 export class BinaryHeap<T> implements Iterable<T> {
   #data: T[] = [];
-  constructor(private compare: (a: T, b: T) => number = descend) {}
-  /** Returns the underlying cloned array in arbitrary order without sorting */
+  #compare: (a: T, b: T) => number;
+
+  /**
+   * Construct an empty binary heap.
+   *
+   * @example Creating an empty binary heap
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = new BinaryHeap<number>();
+   * ```
+   *
+   * @example Creating a binary heap with a custom comparison function
+   * ```ts
+   * import { BinaryHeap, ascend } from "@std/data-structures";
+   * const heap = new BinaryHeap(ascend);
+   * ```
+   *
+   * @param compare A custom comparison function to sort the values in the heap. By default, the values are sorted in descending order.
+   */
+  constructor(compare: (a: T, b: T) => number = descend) {
+    this.#compare = compare;
+  }
+
+  /**
+   * Returns the underlying cloned array in arbitrary order without sorting.
+   *
+   * @example Getting the underlying array
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = BinaryHeap.from([4, 1, 3, 5, 2]);
+   * heap.toArray(); // [ 5, 4, 3, 1, 2 ]
+   * ```
+   *
+   * @returns An array containing the values in the binary heap.
+   */
   toArray(): T[] {
     return Array.from(this.#data);
   }
-  /** Creates a new binary heap from an array like or iterable object. */
-  static from<T>(
-    collection: ArrayLike<T> | Iterable<T> | BinaryHeap<T>,
-  ): BinaryHeap<T>;
+
+  /**
+   * Creates a new binary heap from an array like, an iterable object, or an
+   * existing binary heap.
+   *
+   * A custom comparison function can be provided to sort the values in a
+   * specific order. By default, the values are sorted in descending order,
+   * unless a {@link BinaryHeap} is passed, in which case the comparison
+   * function is copied from the input heap.
+   *
+   * @example Creating a binary heap from an array like
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = BinaryHeap.from([4, 1, 3, 5, 2]);
+   * ```
+   *
+   * @example Creating a binary heap from an iterable object
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = BinaryHeap.from((function*() { yield* [4, 1, 3, 5, 2]; })());
+   * ```
+   *
+   * @example Creating a binary heap from an existing binary heap
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = BinaryHeap.from([4, 1, 3, 5, 2]);
+   * const copy = BinaryHeap.from(heap);
+   * ```
+   *
+   * @example Creating a binary heap from an array like with a custom comparison function
+   * ```ts
+   * import { BinaryHeap, ascend } from "@std/data-structures";
+   * const heap = BinaryHeap.from([4, 1, 3, 5, 2], { compare: ascend });
+   * ```
+   *
+   * @typeparam T The type of the values stored in the binary heap.
+   * @param collection An array like, an iterable object, or an existing binary heap.
+   * @param options An optional options object to customize the comparison function.
+   */
   static from<T>(
     collection: ArrayLike<T> | Iterable<T> | BinaryHeap<T>,
-    options: {
+    options?: {
       compare?: (a: T, b: T) => number;
     },
   ): BinaryHeap<T>;
-  static from<T, U, V>(
+  /**
+   * Creates a new binary heap from an array like, an iterable object, or an
+   * existing binary heap.
+   *
+   * A custom mapping function can be provided to transform the values before
+   * inserting them into the heap.
+   *
+   * A custom comparison function can be provided to sort the values in a
+   * specific order. By default, the values are sorted in descending order,
+   * unless a {@link BinaryHeap} is passed, in which case the comparison
+   * function is copied from the input heap. The comparison operator is used to
+   * sort the values in the heap after mapping the values.
+   *
+   * @example Creating a binary heap from an array like with a custom mapping function
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = BinaryHeap.from([4, 1, 3, 5, 2], { map: (value) => value * 2 });
+   * ```
+   *
+   * @typeparam T The type of the values in the passed collection.
+   * @typeparam U The type of the values stored in the binary heap.
+   * @typeparam V The type of the `this` value when calling the mapping function. Defaults to `undefined`.
+   * @param collection An array like, an iterable object, or an existing binary heap.
+   * @param options The options object to customize the mapping and comparison functions. The `thisArg` property can be used to set the `this` value when calling the mapping function.
+   */
+  static from<T, U, V = undefined>(
     collection: ArrayLike<T> | Iterable<T> | BinaryHeap<T>,
     options: {
       compare?: (a: U, b: U) => number;
@@ -94,7 +189,7 @@ export class BinaryHeap<T> implements Iterable<T> {
     let unmappedValues: ArrayLike<T> | Iterable<T> = [];
     if (collection instanceof BinaryHeap) {
       result = new BinaryHeap(
-        options?.compare ?? (collection as unknown as BinaryHeap<U>).compare,
+        options?.compare ?? (collection as unknown as BinaryHeap<U>).#compare,
       );
       if (options?.compare || options?.map) {
         unmappedValues = collection.#data;
@@ -114,17 +209,67 @@ export class BinaryHeap<T> implements Iterable<T> {
     return result;
   }
 
-  /** The amount of values stored in the binary heap. */
+  /**
+   * The count of values stored in the binary heap.
+   *
+   * The complexity of this operation is O(1).
+   *
+   * @returns The count of values stored in the binary heap.
+   */
   get length(): number {
     return this.#data.length;
   }
 
-  /** Returns the greatest value in the binary heap, or undefined if it is empty. */
+  /**
+   * Get the greatest value from the binary heap without removing it, or
+   * undefined if the heap is empty.
+   *
+   * The complexity of this operation is O(1).
+   *
+   * @example Getting the greatest value from the binary heap
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = BinaryHeap.from([4, 1, 3, 5, 2]);
+   * heap.peek(); // 5
+   * ```
+   *
+   * @example Getting the greatest value from an empty binary heap
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = new BinaryHeap<number>();
+   * heap.peek(); // undefined
+   * ```
+   *
+   * @returns The greatest value from the binary heap, or undefined if it is empty.
+   */
   peek(): T | undefined {
     return this.#data[0];
   }
 
-  /** Removes the greatest value from the binary heap and returns it, or null if it is empty. */
+  /**
+   * Remove the greatest value from the binary heap and return it, or return
+   * undefined if the heap is empty.
+   *
+   * @example Removing the greatest value from the binary heap
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = BinaryHeap.from([4, 1, 3, 5, 2]);
+   * heap.pop(); // 5
+   * [...heap]; // [ 4, 3, 2, 1 ]
+   * ```
+   *
+   * The complexity of this operation is on average and worst case O(log n),
+   * where n is the count of values stored in the binary heap.
+   *
+   * @example Removing the greatest value from an empty binary heap
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = new BinaryHeap<number>();
+   * heap.pop(); // undefined
+   * ```
+   *
+   * @returns The greatest value from the binary heap, or undefined if the heap is empty.
+   */
   pop(): T | undefined {
     const size: number = this.#data.length - 1;
     swap(this.#data, 0, size);
@@ -133,10 +278,10 @@ export class BinaryHeap<T> implements Iterable<T> {
     let left: number = right - 1;
     while (left < size) {
       const greatestChild = right === size ||
-          this.compare(this.#data[left]!, this.#data[right]!) <= 0
+          this.#compare(this.#data[left]!, this.#data[right]!) <= 0
         ? left
         : right;
-      if (this.compare(this.#data[greatestChild]!, this.#data[parent]!) < 0) {
+      if (this.#compare(this.#data[greatestChild]!, this.#data[parent]!) < 0) {
         swap(this.#data, parent, greatestChild);
         parent = greatestChild;
       } else {
@@ -148,14 +293,32 @@ export class BinaryHeap<T> implements Iterable<T> {
     return this.#data.pop();
   }
 
-  /** Adds values to the binary heap. */
+  /**
+   * Add one or more values to the binary heap, returning the new length of the
+   * heap.
+   *
+   * The complexity of this operation is O(1) on average and O(log n) in the
+   * worst case, where n is the count of values stored in the binary heap.
+   *
+   * @example Adding values to the binary heap
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = BinaryHeap.from([4, 1, 3, 2]);
+   * heap.push(5);
+   * [...heap]; // [ 5, 4, 3, 1, 2 ]
+   * ```
+   *
+   * @param values The values to add to the binary heap.
+   * @returns The new length of the binary heap.
+   */
   push(...values: T[]): number {
     for (const value of values) {
       let index: number = this.#data.length;
       let parent: number = getParentIndex(index);
       this.#data.push(value);
       while (
-        index !== 0 && this.compare(this.#data[index]!, this.#data[parent]!) < 0
+        index !== 0 &&
+        this.#compare(this.#data[index]!, this.#data[parent]!) < 0
       ) {
         swap(this.#data, parent, index);
         index = parent;
@@ -165,23 +328,78 @@ export class BinaryHeap<T> implements Iterable<T> {
     return this.#data.length;
   }
 
-  /** Removes all values from the binary heap. */
+  /**
+   * Remove all values from the binary heap.
+   *
+   * @example Clearing the binary heap
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = BinaryHeap.from([4, 1, 3, 5, 2]);
+   * heap.clear();
+   * [...heap]; // []
+   * ```
+   */
   clear() {
     this.#data = [];
   }
 
-  /** Checks if the binary heap is empty. */
+  /**
+   * Check if the binary heap is empty.
+   *
+   * @example Checking if the binary heap is empty
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = new BinaryHeap<number>();
+   * heap.isEmpty(); // true
+   * heap.push(42);
+   * heap.isEmpty(); // false
+   * ```
+   *
+   * @returns true if the binary heap is empty, otherwise false.
+   */
   isEmpty(): boolean {
     return this.#data.length === 0;
   }
 
-  /** Returns an iterator for retrieving and removing values from the binary heap. */
+  /**
+   * Create an iterator that retrieves values from the binary heap in order
+   * from greatest to least. The binary heap is drained in the process.
+   *
+   * To avoid draining the binary heap, create a copy using
+   * {@link BinaryHeap.from} and then call {@link BinaryHeap#drain} on the copy.
+   *
+   * @example Draining the binary heap
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = BinaryHeap.from([4, 1, 3, 5, 2]);
+   * [...heap.drain()]; // [ 5, 4, 3, 2, 1 ]
+   * [...heap.drain()]; // []
+   * ```
+   *
+   * @returns An iterator for retrieving and removing values from the binary heap.
+   */
   *drain(): IterableIterator<T> {
     while (!this.isEmpty()) {
       yield this.pop() as T;
     }
   }
 
+  /**
+   * Create an iterator that retrieves values from the binary heap in order
+   * from greatest to least. The binary heap is drained in the process.
+   *
+   * See {@link BinaryHeap#values}.
+   *
+   * @example Getting an iterator for the binary heap
+   * ```ts
+   * import { BinaryHeap } from "@std/data-structures";
+   * const heap = BinaryHeap.from([4, 1, 3, 5, 2]);
+   * [...heap]; // [ 5, 4, 3, 2, 1 ]
+   * [...heap]; // []
+   * ```
+   *
+   * @returns An iterator for retrieving and removing values from the binary heap.
+   */
   *[Symbol.iterator](): IterableIterator<T> {
     yield* this.drain();
   }