async_before_it_became_a_mainstream.js

Last login: Sat Dec 15 20:13:38 on ttys000

~
➜ node
> function* gf() {
... let a = yield 1;
... console.log('a:', a);
... let b = yield 2;
... console.log('b:', b);
... return 3;
... }
undefined
> g = gf();
Object [Generator] {}
> g
Object [Generator] {}
> g.next()
{ value: 1, done: false }
> g.next()
a: undefined
{ value: 2, done: false }
> g.next()
b: undefined
{ value: 3, done: true }
> g = gf();
Object [Generator] {}
> g.next(100)
{ value: 1, done: false }
> g.next(200)
a: 200
{ value: 2, done: false }
> g.next(300)
b: 300
{ value: 3, done: true }
> g = gf();
Object [Generator] {}
> g.
g.__defineGetter__      g.__defineSetter__      g.__lookupGetter__
g.__lookupSetter__      g.__proto__             g.hasOwnProperty
g.isPrototypeOf         g.propertyIsEnumerable  g.toLocaleString
g.toString              g.valueOf

g.constructor           g.next                  g.return
g.throw

> g.throw(10)
Thrown: 10
> g.next(300)
{ value: undefined, done: true }
> g.next(300)
{ value: undefined, done: true }
> g.next(300)
{ value: undefined, done: true }
> function* f() {
...
> let t = n => new Promise(res => setTimeout(() => res(100), n);
let t = n => new Promise(res => setTimeout(() => res(100), n);
                                                            ^

SyntaxError: missing ) after argument list

> let t = n => new Promise(res => setTimeout(() => res(100), n));
undefined
> p=t(2000)
Promise {
  <pending>,
  domain:
   Domain {
     domain: null,
     _events:
      { removeListener: [Function: updateExceptionCapture],
        newListener: [Function: updateExceptionCapture],
        error: [Function: debugDomainError] },
     _eventsCount: 3,
     _maxListeners: undefined,
     members: [] } }
> t(2000).then(x=>console.log(x));
Promise {
  <pending>,
  domain:
   Domain {
     domain: null,
     _events:
      { removeListener: [Function: updateExceptionCapture],
        newListener: [Function: updateExceptionCapture],
        error: [Function: debugDomainError] },
     _eventsCount: 3,
     _maxListeners: undefined,
     members: [] } }
> 100

> gg = function* () {
... let a = yield t(2000);
... console.log('a', a);
... }
[GeneratorFunction: gg]
> g=gg();
Object [Generator] {}
> z=g.next()
{ value:
   Promise {
     <pending>,
     domain:
      Domain {
        domain: null,
        _events: [Object],
        _eventsCount: 3,
        _maxListeners: undefined,
        members: [] } },
  done: false }
> z.then(v => g.next(v));
TypeError: z.then is not a function
> z
{ value:
   Promise {
     100,
     domain:
      Domain {
        domain: null,
        _events: [Object],
        _eventsCount: 3,
        _maxListeners: undefined,
        members: [] } },
  done: false }
> z.value.then(v => g.next(v));
Promise {
  <pending>,
  domain:
   Domain {
     domain: null,
     _events:
      { removeListener: [Function: updateExceptionCapture],
        newListener: [Function: updateExceptionCapture],
        error: [Function: debugDomainError] },
     _eventsCount: 3,
     _maxListeners: undefined,
     members: [] } }
> a 100

> mkdir gen
mkdir gen
      ^^^

SyntaxError: Unexpected identifier

> %

~ took 11m 56s
➜ mkdir gen

~
➜ xs gen
zsh: command not found: xs

~
➜ cd gen

~/gen
➜ npm init -y
Wrote to /Users/tieorange/gen/package.json:

{
  "name": "gen",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC"
}



~/gen is 📦 v1.0.0 via ⬢ v10.10.0
➜ npm i bluebird
npm notice created a lockfile as package-lock.json. You should commit this file.
npm WARN [email protected] No description
npm WARN [email protected] No repository field.

+ [email protected]
added 1 package from 1 contributor and audited 1 package in 1.784s
found 0 vulnerabilities


~/gen is 📦 v1.0.0 via ⬢ v10.10.0 took 2s
➜ node
> const { coroutine } = require('bluebird');
undefined
> f = coroutine(function* () {
... console.log('a'); let a = yield t(3000);
... console.log('b', a);
... }
... );
[Function]
> f();
a
Promise {
  _bitField: 17825792,
  _fulfillmentHandler0:
   ReferenceError: t is not defined
       at repl:2:27
       at Generator.next (<anonymous>)
       at Generator.tryCatcher (/Users/tieorange/gen/node_modules/bluebird/js/release/util.js:16:23)
       at PromiseSpawn._promiseFulfilled (/Users/tieorange/gen/node_modules/bluebird/js/release/generators.js:97:49)
       at /Users/tieorange/gen/node_modules/bluebird/js/release/generators.js:201:15
       at repl:1:1
       at Script.runInThisContext (vm.js:96:20)
       at REPLServer.defaultEval (repl.js:329:29)
       at bound (domain.js:396:14)
       at REPLServer.runBound [as eval] (domain.js:409:12)
       at REPLServer.onLine (repl.js:627:10)
       at REPLServer.emit (events.js:187:15)
       at REPLServer.EventEmitter.emit (domain.js:442:20)
       at REPLServer.Interface._onLine (readline.js:290:10)
       at REPLServer.Interface._line (readline.js:638:8)
       at REPLServer.Interface._ttyWrite (readline.js:919:14),
  _rejectionHandler0: undefined,
  _promise0: undefined,
  _receiver0: undefined }
> Unhandled rejection ReferenceError: t is not defined
    at repl:2:27
    at Generator.next (<anonymous>)
    at Generator.tryCatcher (/Users/tieorange/gen/node_modules/bluebird/js/release/util.js:16:23)
    at PromiseSpawn._promiseFulfilled (/Users/tieorange/gen/node_modules/bluebird/js/release/generators.js:97:49)
    at /Users/tieorange/gen/node_modules/bluebird/js/release/generators.js:201:15
    at repl:1:1
    at Script.runInThisContext (vm.js:96:20)
    at REPLServer.defaultEval (repl.js:329:29)
    at bound (domain.js:396:14)
    at REPLServer.runBound [as eval] (domain.js:409:12)
    at REPLServer.onLine (repl.js:627:10)
    at REPLServer.emit (events.js:187:15)
    at REPLServer.EventEmitter.emit (domain.js:442:20)
    at REPLServer.Interface._onLine (readline.js:290:10)
    at REPLServer.Interface._line (readline.js:638:8)
    at REPLServer.Interface._ttyWrite (readline.js:919:14)


(To exit, press ^C again or type .exit)
> let t = n => new Promise(res => setTimeout(() => res(100), n));
undefined
> f();
a
Promise {
  _bitField: 0,
  _fulfillmentHandler0: undefined,
  _rejectionHandler0: undefined,
  _promise0: undefined,
  _receiver0: undefined }
> b 100

>
(To exit, press ^C again or type .exit)
> async function af() {
... console.log('a');
... let a = await t();
...
...
> async function af() {
... console.log('a');
... let a = await t(3000);
... console.log('b', a);
... }
undefined
> af();
a
Promise {
  <pending>,
  domain:
   Domain {
     domain: null,
     _events:
      { removeListener: [Function: updateExceptionCapture],
        newListener: [Function: updateExceptionCapture],
        error: [Function: debugDomainError] },
     _eventsCount: 3,
     _maxListeners: undefined,
     members: [] } }
> b 100
> (async () => { console.log('x'); await af(); console.log('y'); })();
x
a
Promise {
  <pending>,
  domain:
   Domain {
     domain: null,
     _events:
      { removeListener: [Function: updateExceptionCapture],
        newListener: [Function: updateExceptionCapture],
        error: [Function: debugDomainError] },
     _eventsCount: 3,
     _maxListeners: undefined,
     members: [] } }
> b 100
y

> f = coroutine(function* () {
... ... console.log('a'); let a = yield t(3000);
... console.log('a'); let a = yield t(3000);
^^^

SyntaxError: Unexpected token ...

> ... console.log('b', a);
... console.log('b', a);
^^^

SyntaxError: Unexpected token ...

> ... }
... }
    ^

SyntaxError: Unexpected token }

> (async () => { console.log('x'); await f(); console.log('y'); })();
x
a
Promise {
  <pending>,
  domain:
   Domain {
     domain: null,
     _events:
      { removeListener: [Function: updateExceptionCapture],
        newListener: [Function: updateExceptionCapture],
        error: [Function: debugDomainError] },
     _eventsCount: 3,
     _maxListeners: undefined,
     members: [] } }
> b 100
y

> (async () => { for (let i = 0; i < 10; i++) { console.log('x'); await af(); } })();
x
a
Promise {
  <pending>,
  domain:
   Domain {
     domain: null,
     _events:
      { removeListener: [Function: updateExceptionCapture],
        newListener: [Function: updateExceptionCapture],
        error: [Function: debugDomainError] },
     _eventsCount: 3,
     _maxListeners: undefined,
     members: [] } }
> b 100
x
a
b 100
x
a
b 100
x
a

> ddddb 100
x
a
> b 100
x
a
b 100
x
a
dddb 100
x
a
> b 100
x
a
b 100
x
a

>
> b 100

>
> x1 = (async () => { for (let i = 0; i < 10; i++) { console.log('x'); await af(); } });
[AsyncFunction: x1]
> x2 = (async () => { for (let i = 0; i < 10; i++) { console.log('y'); await f(); } });
[AsyncFunction: x2]
>
>
> x1(); x2();
x
a
y
a
Promise {
  <pending>,
  domain:
   Domain {
     domain: null,
     _events:
      { removeListener: [Function: updateExceptionCapture],
        newListener: [Function: updateExceptionCapture],
        error: [Function: debugDomainError] },
     _eventsCount: 3,
     _maxListeners: undefined,
     members: [] } }
>
>
>
> b 100
x
a
b 100
y
a
b 100
x
a
b 100
y
a
b 100
x
a
b 100
y
a
b 100
x
a
b 100
y
a
b 100
x
a
b 100
y
a
b 100
x
a
b 100
y
a
b 100
x
a
b 100
y
a
b 100
x
a
b 100
y
a
b 100
x
a
b 100
y
a
b 100
b 100