Add module and .d.ts typings

Author: tshemsedinov

TypeScript/queue.d.ts

@@ -0,0 +1,12 @@
+interface UnrolledQueueOptions {
+  nodeSize?: number;
+}
+
+declare class UnrolledQueue<T = any> {
+  constructor(options?: UnrolledQueueOptions);
+
+  readonly length: number;
+
+  enqueue(item: T): void;
+  dequeue(): T | null;
+}

TypeScript/queue.js

@@ -0,0 +1,68 @@
+'use strict';
+
+class QueueNode {
+  constructor({ size }) {
+    this.length = 0;
+    this.size = size;
+    this.readIndex = 0;
+    this.writeIndex = 0;
+    this.buffer = new Array(size);
+    this.next = null;
+  }
+
+  enqueue(item) {
+    if (this.length === this.size) return false;
+    this.buffer[this.writeIndex++] = item;
+    this.length++;
+    return true;
+  }
+
+  dequeue() {
+    if (this.length === 0) return null;
+    const item = this.buffer[this.readIndex++];
+    this.length--;
+    return item;
+  }
+}
+
+class UnrolledQueue {
+  #length = 0;
+  #nodeSize = 2048;
+  #head = null;
+  #tail = null;
+
+  constructor(options = {}) {
+    const { nodeSize } = options;
+    if (nodeSize) this.#nodeSize = nodeSize;
+    const node = new QueueNode({ size: nodeSize });
+    this.#head = node;
+    this.#tail = node;
+  }
+
+  get length() {
+    return this.#length;
+  }
+
+  enqueue(item) {
+    if (!this.#head.enqueue(item)) {
+      const node = new QueueNode({ size: this.#nodeSize });
+      this.#head.next = node;
+      this.#head = node;
+      this.#head.enqueue(item);
+    }
+    this.#length++;
+  }
+
+  dequeue() {
+    const item = this.#tail.dequeue();
+    if (item !== null) {
+      this.#length--;
+      if (this.#tail.length === 0 && this.#tail.next) {
+        this.#tail = this.#tail.next;
+      }
+    }
+    return item;
+  }
+}
+
+module.exports = { UnrolledQueue };

TypeScript/usage.js

@@ -0,0 +1,23 @@
+'use strict';
+
+const { UnrolledQueue } = require('./queue.js');
+
+const mq = new UnrolledQueue({ nodeSize: 8 });
+
+for (let id = 0; id < 5; id++) {
+  mq.enqueue({ id });
+}
+
+while (mq.length) {
+  const task = mq.dequeue();
+  console.log(`Processing ${task.id}`);
+}
+
+for (let id = 100; id < 105; id++) {
+  mq.enqueue({ id });
+}
+
+while (mq.length) {
+  const task = mq.dequeue();
+  console.log(`Processing ${task.id}`);
+}