Function map

src/cursor/abstract_cursor.ts:739–751

* Map all documents using the provided function * If there is a transform set on the cursor, that will be called first and the result passed to * this function's transform. * * @remarks * * **Note** Cursors use `null` internally to indicate that there are no more documents in the c

(transform: (doc: TSchema) => T)

   * @param transform - The mapping transformation method.
   */
  map<T = any>(transform: (doc: TSchema) => T): AbstractCursor<T> {
    this.throwIfInitialized();
    const oldTransform = this.transform;
    if (oldTransform) {
      this.transform = doc => {
        return transform(oldTransform(doc));
      };
    } else {
      this.transform = transform;
    }

    return this as unknown as AbstractCursor<T>;
  }

  /**
   * Set the ReadPreference for the cursor.