function * fn() { console.log('hello'); return 'Joh';}// 執(zhí)行fn()時不會直接執(zhí)行方法體中的代碼，它會返回一個指針, 這個指針實現(xiàn)了 interator接口，也就是返回一個interator對象let it = fn();// 通過調(diào)用next就會執(zhí)行方法體, 返回結(jié)果是 {value:'Joh', done:true}, 其中next返回的是函數(shù)體中return的值let res = it.next();console.log(res);

function * fn() {  // 和yield相配合，把一個generator內(nèi)部分為幾個斷點來執(zhí)行，每個斷點就是yield語句  // 注意 yield和return的區(qū)別： yield可以有多個，return只能有1個  yield 1;  yield 2;  yield 3;  return 4; // 可以沒有return值，done為true的value將會是undefined}let it = fn();// 在for-of 循環(huán)中只能打印done為false的value值，done為true時,程序終止for(let v of it) {  console.log(v); // 分別輸出 1 2 3}

function * fn(_name) { let name = yield _name; // yield 的默認值為undefined return name;}let it = fn('Joh');console.log(it.next()); // {value:'Joh', done:false}console.log(it.next('Tom')); // {value:'Tom', done:true} // 此處value應(yīng)該為undefined，但是通過next參數(shù)的形式賦值改變了最后一個值console.log(it.next('Lily')); // {value: undefined, done:true} // 已經(jīng)循環(huán)完畢，即使傳值也是undefined

function sum(a, b) { return a + b;}function * fn() { let res = sum(yield 1, 5 + (yield 3)); console.log(res); console.log('my qq: ' + (yield qq)); // yield 在一個語句中需要括起來}fn();

function * fn() { let qq = yield; // yield 默認返回undefined, 不會拋出異常 console.log(qq);}let g = fn();g.next(); // 第一個斷點沒有輸出// g.next('qq 11111'); // 完畢之后傳值輸出：qq 11111g.throw('error!'); // Uncaught error!

function * fn() { let qq; try {  qq = yield; // yield 默認返回undefined }catch(e){  console.log('qq have error'); }finally{  console.log(qq); }}let g = fn();g.next();g.throw('error!');// qq have error// undefined

function * fn() { let qq; qq = yield; console.log(qq);}let g = fn();g.next();try{ g.throw('error!');}catch(e){ console.log('qq have error!');}

function * fn() { let qq; try {  qq = yield ff; // ff 未定義, 所以qq不會被正確賦值 此處是非 yield 的異常 }catch(e){  console.log('err1'); } console.log(qq);}let g = fn();g.next();g.next('qq 5554');// err1// undefined

function asyncF(name) { return new Promise(function(resolve){  setTimeout(function(){   resolve('my name is ' + name);  }); });}function * fn() { console.log(yield asyncF('Joh'));}let gf = fn();function exec(gf,value) { let res = gf.next(value); if(!res.done) {  if(res.value instanceof Promise) {   res.value.then(function (v) {    exec(gf, v);   })  }else{   exec(gf, res.value);  } }}exec(gf); // my name is Joh

function asyncF(name) { return new Promise(function(resolve){  setTimeout(function(){   resolve('my name is ' + name);  }); });}function sum(a, b) { return new Promise(function (resolve) {  setTimeout(function () {    resolve(a + b);  }); })}function * fn(name) { if((yield sum(3,5)) > 6) {  console.log(yield asyncF(name)); }else{  console.log('error'); }}let gf = fn('Joh');// generator 執(zhí)行器 相當(dāng)于 tj/co 模塊function exec(gf,value) { let res = gf.next(value); if(!res.done) {  if(res.value instanceof Promise) {   res.value.then(function (v) {    exec(gf, v);   })  }else{   exec(gf, res.value);  } }}exec(gf); // my name is Joh

function asyncF(name) { return new Promise(function(resolve){  setTimeout(function(){   resolve('my name is ' + name);  }); });}function sum(a, b) { return new Promise(function (resolve) {  setTimeout(function () {    resolve(a + b);  }); })}function fn(name) { sum(3,5)  .then(function (num) {   if(num > 6) {    asyncF(name)     .then(function (v) {      console.log(v);     })   }else{    console.log('error');   }  })}fn('Joh');

var co = require('co');function asyncF(name) { return new Promise(function(resolve){  setTimeout(function(){   resolve('my name is ' + name);  }); });}function sum(a, b) { return new Promise(function (resolve) {  setTimeout(function () {    resolve(a + b);  }); })}function * fn(name) { if((yield sum(3,5)) > 6) {  console.log(yield asyncF(name)); }else{  console.log('error'); }}var fnx = co.wrap(fn);fnx('Joh'); // my name is Joh