The iterable interface defines the behavior of an iteration, using the for…of to show the values looped in the mentioned construct. Now, let’s use the iterator this time below: const it = makeRangeIterator(1, 5, 2) Ĭonsole.log(“Iterated over sequence of size: “, result.value) įrom both examples, do remember it is not possible to find out if an object is an iterator. The example below shows how implementing iterable can provide a continuous loop of code: Using the erator function, we are given the next() function. eratorĪ JavaScript iterable object has erator as mentioned earlier. However, this feature is not favored all the time as this does not support for…of loop statements. The behavior of next() method can be shown in the example below: ĭocument.getElementById(“demo”).innerHTML = n.next().value Īs we can see, the process is never-ending when next() is introduced. Home MadeĪs we mentioned earlier, iterable object have this continuous running feature hence, the home made iterable keeps running one next() is called. If the result is false, there must be a new value given by the iterator. Meanwhile, the done returns true upon completion of the iterable object. The value can be removed if done comes true, normally it is returned by the iterator. This is done by using the next() method, which returns two properties of an object: value and done. By learning how to produce the sequence of values from this object, we can transform such objects into an iterable interface. We must keep in mind that iterator protocols outline the production of an iterable object. In this example, we are iterating over an array: In this example, we are using iterable over a string:ĭocument.getElementById(“demo”).innerHTML = text įor arrays as well, we can use for…of loop for implementing iterable as illustrated in the example below: Implementing iterable over elements of a string would be as follows: Let’s see how to iterate over a string to start with the basics. When working with the iterable interface, consider the iterable object iterates with for…of where we must use the erator method.

For iterator javascript