ES8 and earlier versions introduced new object interfaces and loops for iteration. The addition of the new iteration protocols opens up a new world of algorithms and abilities for JavaScript. We will start the chapter by introducing the symbols and various properties of the Symbol object. We will also learn how execution stacks are created for the nested function calls, their impacts, and how to optimize their performance and memory usage.
Although symbols are a separate topic to iterators, we will still be covering symbols in this chapter, because to implement the iterable protocol, you need to use symbols.
In this chapter, we'll cover:
- Using symbols as the object property keys
- Implementing the iteration protocols in objects
- Creating and using the generator object
- Using the for…of loop for iterating
- The tail call optimization
