Javascript String iterator

Introduction

The string prototype has an @@iterator method. 

str[Symbol.iterator]

We can iterate through individual characters.

Manual use of the iterator works as follows: 

let message = "abc"; 
let stringIterator = message[Symbol.iterator](); 
              /*from www.j av a2  s .  c  om*/
console.log(stringIterator.next());  // {value: "a", done: false} 
console.log(stringIterator.next());  // {value: "b", done: false} 
console.log(stringIterator.next());  // {value: "c", done: false} 
console.log(stringIterator.next());  // {value: undefined, done: true}

When used in a for of loop, the loop will use this iterator to visit each character in order: 

for (const c of "abcde") {
    console.log(c);/*w  ww .jav a 2  s . co m*/
}

The string iterator allows for interoperability with the destructuring operator.

This allows you to split a string by its characters: 

let message = "abcde"; 

console.log([...message]);  // ["a", "b", "c", "d", "e"]



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