Change iteration implementation to elimate a private property and make the object re-iterable.

Author: gabesullice

linkset/src/core/linkset.ts

@@ -67,14 +67,12 @@ export interface NormalizableLinksetInterface<T extends NormalizedLinksetInterfa
  * A set of links.
  * @internal
  */
-export class Linkset implements NormalizableLinksetInterface<NormalizedLinksetInterface>, IterableIterator<LinkInterface> {
+export class Linkset implements NormalizableLinksetInterface<NormalizedLinksetInterface> {
   /**
    * {@inheritDoc LinksetInterface.elements}
    */
   readonly elements: LinkInterface[];
-  private iterationIndex: number;
   constructor(links: LinkInterface[]) {
-    this.iterationIndex = 0;
     this.elements = links;
   }
   /**
@@ -108,20 +106,20 @@ export class Linkset implements NormalizableLinksetInterface<NormalizedLinksetIn
     return new Linkset(this.elements.filter((link) => link.anchor === anchor));
   }
   /**
-   * Implements the IterableIterator interface.
+   * Implements the iterable protocol.
    */
-  [Symbol.iterator](): IterableIterator<LinkInterface> {
-    return this;
-  }
-  /**
-   * Implements the IterableIterator interface.
-   */
-  next(): IteratorResult<LinkInterface> {
-    if (this.iterationIndex < this.elements.length) {
-      return {value: this.elements[this.iterationIndex++], done: false};
-    } else {
-      return {value: undefined, done: true};
-    }
+  [Symbol.iterator](): Iterator<LinkInterface> {
+    const elems = this.elements;
+    let pointer = 0;
+    return {
+      next(): IteratorResult<LinkInterface> {
+        if (pointer < elems.length) {
+          return {value: elems[pointer++], done: false};
+        } else {
+          return {value: undefined, done: true};
+        }
+      }
+    };
   }
   /**
    * {@inheritDoc NormalizableLinksetInterface.normalize}

linkset/src/index.test.ts

@@ -27,6 +27,10 @@ describe('Linkset', () => {
     expect(linkset.linksFrom('https://example.org/article/view/7507').size).toBe(4);
     expect(linkset.linksFrom('https://example.com/links/article/7507').size).toBe(1);
   });
+  it('should be iterable and re-iterable', () => {
+    expect(Array.from(linkset).length).toBe(5);
+    expect(Array.from(linkset).length).toBe(5);
+  });
   it('should be re-normalizable', () => {
     const linkset = denormalize(JSON.parse(examples['Figure 4']));
     expect(JSON.stringify(linkset.normalize())).toBe(examples['Figure 4']);