1.
Past and Future of
Asynchronous Javascript

2.
: @brn ( )
:
: Cyberagent RightSegment AI Messenger
: http://abcdef.gets.b6n.ch/

3.
What is Asynchronous?
javascript javascript stack
stack

4.
What is Asynchronous?
ee..gg.. sseettTTiimmeeoouutt
setTimeout

5.
Callback
javascript
someAsyncJob(function() {…});

6.
jQuery.Deferred
jQuery Deferred
function delayHello() {
var d = new $.Deferred;
setTimeout(function(){
d.resolve('Hello');
}, 1000);
return d.promise();
}
delayHello().done(function(word) {console.log(word)})

7.
Promise/A+
Nodejs Web js CommonJS
Q
Q.fcall(promisedStep1)
.then(promisedStep2)
.then(promisedStep3)
.then(promisedStep4)
.then(function (value4) {
// Do something with value4
})
.catch(function (error) {
// Handle any error from all above steps
})
.done();

8.
Promise
Ecmascript Promise
const p = new Promise((resolve, reject) => {
setTimeout(() => resolve('hello'));
});
p.then(word => console.log(word));

9.
Problems
Promise
const p = new Promise(resolve => {
setTimeout(() => resolve('hello'));
})
p.then(word => {
setTimeout(() => resolve(`${word} world`));
})
.then(word => console.log(word));

10.
Generator & co
Generator Ecmascript
Generator co
const hello = () => new Promise(resolve => {
setTimeout(() => resolve("hello"), 300);
});
const world = () => new Promise(resolve => {
setTimeout(() => resolve("world"), 300);
});
co(function* () {
var hello = yield hello();
var world = yield world();
return `${hello} ${world}`;
}).then(word => console.log(value));

11.
async & await
async await ES7
Promise
async helloWorld() {
const hello = await new Promise(resolve => {
setTimeout(() => resolve('hello'));
});
const word = await new Promise(resolve => {
setTimeout(() => resolve('world'));
});
console.log(`${hello} ${world}`)
}

12.
Asynchronous Iterators
async await
Asynchronous Iterators Stage3
async function* readLines(path) {
let file = await fileOpen(path);
try {
while (!file.EOF) {
yield await file.readLine();
}
} finally {
await file.close();
}
}
for await (const line of readLines(filePath)) {
console.log(line);
}

13.
• Babel typescript async await
• JS Bluebird
• Promise
https://gist.github.com/brn/4f639a5bdb845f0aebe8e0725691a442