feat(collections): add new collection APIs, iterator support, and tree serialization utilities

ts/classes.limitedarray.ts

@@ -7,6 +7,10 @@ export class LimitedArray<T> {
     this.arrayLimit = limitArg;
   }
 
+  public get length(): number {
+    return this.array.length;
+  }
+
   addOne(objectArg: T) {
     this.array.unshift(objectArg);
     if (this.array.length > this.arrayLimit) {
@@ -28,6 +32,9 @@ export class LimitedArray<T> {
   }
 
   getAverage(): number {
+    if (this.array.length === 0) {
+      return 0;
+    }
     if (typeof this.array[0] === 'number') {
       let sum = 0;
       for (let localNumber of this.array) {
@@ -39,4 +46,25 @@ export class LimitedArray<T> {
       return null;
     }
   }
+
+  remove(item: T): boolean {
+    const idx = this.array.indexOf(item);
+    if (idx !== -1) {
+      this.array.splice(idx, 1);
+      return true;
+    }
+    return false;
+  }
+
+  clear(): void {
+    this.array.length = 0;
+  }
+
+  getArray(): T[] {
+    return [...this.array];
+  }
+
+  public [Symbol.iterator](): Iterator<T> {
+    return this.array[Symbol.iterator]();
+  }
 }