国产av日韩一区二区三区精品,成人性爱视频在线观看,国产,欧美,日韩,一区,www.成色av久久成人,2222eeee成人天堂

Table of Contents
What is Async Generator?
How to do asynchronous iteration using Async Generator?
What is the difference between Async Generator and ordinary asynchronous functions?
What should you pay attention to when using it?
Home Web Front-end JS Tutorial Asynchronous Iteration with Javascript Async Generators

Asynchronous Iteration with Javascript Async Generators

Jul 06, 2025 am 02:07 AM
Asynchronous iteration

Async Generator is a generator function that supports asynchronous operations. It can generate data while waiting asynchronously, and is suitable for streaming data processing. 1. It is defined by async function*, and can be directly followed by Promise after yield without manual .then(); 2. Use for await...of to consume the data stream it generates, making the code look synchronous but actually execute asynchronously; 3. Unlike ordinary asynchronous functions, it supports the gradual generation and processing of data, saving memory resources; 4. Pay attention to environmental compatibility when using it, and use for await...of to traverse, and exception handling should be cautious, and avoid interrupting the process at will. Async Generator combines the generator's process control and async/await's asynchronous capability, and is suitable for segmented acquisition and streaming scenarios.

Async Iteration with Javascript Async Generators

Asynchronous iteration is especially useful when processing streaming data or getting results step by step, and JavaScript's async generators provide a more natural way to implement it. If you need to generate data while obtaining it asynchronously (such as pulling from API paging, reading large file chunking, etc.), async generator is a very suitable tool.

Async Iteration with Javascript Async Generators

What is Async Generator?

async generator is a generator function that can return a Promise and support await . Its syntax is similar to that of ordinary generators, except that the async keyword is added before it. The value it returns every time it calls next() is a Promise, not a direct { value, done } object.

Async Iteration with Javascript Async Generators

You can define an async generator like this:

 async function* myAsyncGenerator() {
  yield await someAsyncOperation();
}

What's different from ordinary generators is that yield can be followed by Promise, and you don't need to go to .then() manually.

Async Iteration with Javascript Async Generators

How to do asynchronous iteration using Async Generator?

The most common way is to combine for await...of to consume the data stream generated by the async generator. For example, if you want to get the user list by paging, each page will be obtained through fetch:

 async function* fetchUserPages() {
  let page = 1;
  while (true) {
    const res = await fetch(`https://api.example.com/users?page=${page}`);
    const data = await res.json();

    if (data.users.length === 0) break;

    yield data.users;
    page ;
  }
}

//Usage method for await (const users of fetchUserPages()) {
  console.log(users);
}

The benefits of this approach are:

  • The code looks synchronous, but behind it is asynchronous execution.
  • Data comes from pieces one by one, suitable for big data processing.
  • The loop can be interrupted at any time, such as exiting when empty data is encountered.

What is the difference between Async Generator and ordinary asynchronous functions?

Ordinary asynchronous functions return all data at once, while async generator can "wait asynchronously while generating". This is very useful when dealing with large amounts of data or streaming data. For example, you have a large log file that you want to read and analyze by line:

  • Ordinary async functions may have to read the complete file at once before processing, which consumes high memory.
  • async generator can read line by line, process while reading, saving resources.

In addition, async generator supports pause and recovery, controls processes like generators, and also has asynchronous capabilities.

What should you pay attention to when using it?

Although async generator is powerful, there are several details that are easy to ignore during use:

  • Not all environments are fully supported : Node.js and modern browsers are mostly supported, but if you are still maintaining old projects, you have to confirm whether the running environment is compatible.
  • You can't just use normal for...of traversal : you must use for await...of , otherwise you will get a bunch of promises instead of the actual data.
  • Be careful when handling exceptions : errors thrown during asynchronous generation will not be automatically caught. It is recommended to add try/catch inside the generator, or catch errors when traversing externally.
  • Don't return easily, break to consider the status : If you jump out of for await...of , the generator may not have completed the entire process yet, so be careful whether it affects the subsequent logic.

Basically that's it. Async generator combines the generator's process control capabilities and the asynchronous advantages of async/await, and is very suitable for handling scenarios such as segmentation acquisition and streaming. As long as you pay attention to usage and compatibility, you can write clear and efficient asynchronous iterative code.

The above is the detailed content of Asynchronous Iteration with Javascript Async Generators. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undress AI Tool

Undress AI Tool

Undress images for free

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Java vs. JavaScript: Clearing Up the Confusion Java vs. JavaScript: Clearing Up the Confusion Jun 20, 2025 am 12:27 AM

Java and JavaScript are different programming languages, each suitable for different application scenarios. Java is used for large enterprise and mobile application development, while JavaScript is mainly used for web page development.

Mastering JavaScript Comments: A Comprehensive Guide Mastering JavaScript Comments: A Comprehensive Guide Jun 14, 2025 am 12:11 AM

CommentsarecrucialinJavaScriptformaintainingclarityandfosteringcollaboration.1)Theyhelpindebugging,onboarding,andunderstandingcodeevolution.2)Usesingle-linecommentsforquickexplanationsandmulti-linecommentsfordetaileddescriptions.3)Bestpracticesinclud

Javascript Comments: short explanation Javascript Comments: short explanation Jun 19, 2025 am 12:40 AM

JavaScriptcommentsareessentialformaintaining,reading,andguidingcodeexecution.1)Single-linecommentsareusedforquickexplanations.2)Multi-linecommentsexplaincomplexlogicorprovidedetaileddocumentation.3)Inlinecommentsclarifyspecificpartsofcode.Bestpractic

JavaScript Data Types: A Deep Dive JavaScript Data Types: A Deep Dive Jun 13, 2025 am 12:10 AM

JavaScripthasseveralprimitivedatatypes:Number,String,Boolean,Undefined,Null,Symbol,andBigInt,andnon-primitivetypeslikeObjectandArray.Understandingtheseiscrucialforwritingefficient,bug-freecode:1)Numberusesa64-bitformat,leadingtofloating-pointissuesli

JavaScript vs. Java: A Comprehensive Comparison for Developers JavaScript vs. Java: A Comprehensive Comparison for Developers Jun 20, 2025 am 12:21 AM

JavaScriptispreferredforwebdevelopment,whileJavaisbetterforlarge-scalebackendsystemsandAndroidapps.1)JavaScriptexcelsincreatinginteractivewebexperienceswithitsdynamicnatureandDOMmanipulation.2)Javaoffersstrongtypingandobject-orientedfeatures,idealfor

How to work with dates and times in js? How to work with dates and times in js? Jul 01, 2025 am 01:27 AM

The following points should be noted when processing dates and time in JavaScript: 1. There are many ways to create Date objects. It is recommended to use ISO format strings to ensure compatibility; 2. Get and set time information can be obtained and set methods, and note that the month starts from 0; 3. Manually formatting dates requires strings, and third-party libraries can also be used; 4. It is recommended to use libraries that support time zones, such as Luxon. Mastering these key points can effectively avoid common mistakes.

JavaScript: Exploring Data Types for Efficient Coding JavaScript: Exploring Data Types for Efficient Coding Jun 20, 2025 am 12:46 AM

JavaScripthassevenfundamentaldatatypes:number,string,boolean,undefined,null,object,andsymbol.1)Numbersuseadouble-precisionformat,usefulforwidevaluerangesbutbecautiouswithfloating-pointarithmetic.2)Stringsareimmutable,useefficientconcatenationmethodsf

Why should you place  tags at the bottom of the ? Why should you place tags at the bottom of the ? Jul 02, 2025 am 01:22 AM

PlacingtagsatthebottomofablogpostorwebpageservespracticalpurposesforSEO,userexperience,anddesign.1.IthelpswithSEObyallowingsearchenginestoaccesskeyword-relevanttagswithoutclutteringthemaincontent.2.Itimprovesuserexperiencebykeepingthefocusonthearticl

See all articles