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MochaãŒPromisesã®ãƒ†ã‚¹ãƒˆã‚’サãƒãƒ¼ãƒˆã—ã¾ã—ãŸ
ã“ã®promiseオブジェクトã¯ã€resolveã™ã‚‹ã®ã§ã€.then ã®ç¬¬ä¸€å¼•æ•°ã§æŒ‡å®šã—ãŸonFulfilled コールãƒãƒƒã‚¯ã« true ã¨ã„ã†å€¤ã‚’渡ã™ã‚ˆã†ã«ãªã£ã¦ã¾ã™ã€‚ 今ã¾ã§ã®ãƒ†ã‚¹ãƒˆã®æ›¸ãæ–¹ ã“ã®getSuccessPromiseã‚’ 1.18.0より以å‰ã¯ä»¥ä¸‹ã®ã‚ˆã†ã«æ›¸ãã“ã¨ã§ãƒ†ã‚¹ãƒˆã‚’ã—ã¦ã„ã¾ã—ãŸã€‚ it("should manually handling test...", function (done) { getSuccessPromise().then(function (value) { assert(value); done(); }).catch(done); // <= ã“ã®catchãŒä»Šå›žã®å¤‰æ›´ã§ã®ç„¦ç‚¹ }); getSuccessPromise()ã®è¿”り値ã§ã‚ã‚‹promiseオブジェクトãŒresolveã•ã‚Œã‚‹ã¨ value ã« true ãŒå…¥ã£ã¦ assert(t
util.promisify ãŒè¿½åŠ ã•ã‚ŒãŸ - from scratch
Node.js ã®ã‚³ã‚¢ã« util.promisify ãŒè¿½åŠ ã•ã‚ŒãŸã€‚ github.com 今回㯠util.promisify ãŒæŒã¤å½¹å‰²ã‚’ä¸å¿ƒã« Node.js ã«ãŠã‘ã‚‹ Promise ã®ç«‹å ´ã«ã¤ã„ã¦ã‚‚話ã—ã¦ã„ã‘ã‚‹ã¨ã„ã„ã¨æ€ã†ã€‚ util.promisify ã¨ã¯ èªã‚“ã§å—ã®ã”ã¨ã関数を Promise ã«å¤‰æ›ã—ã¦ãれるユーティリティメソッド。 下記ã®ã‚ˆã†ãªè¦é ˜ã§å¤‰æ›ã§ãる。 const util = require('util'); const fs = require('fs'); const stat = util.promisify(fs.stat); stat('.').then((stats) => { console.log(stats); }).catch((error) => { console.error(error); }); async-awaitを使ã„ãŸã„
Promise時代ã®JavaScriptã®é–¢æ•°ã®å‡¦ç†/æä¾› - mizchi's blog
最近自分ã§éžåŒæœŸå‰æã®ãƒ—ラグイン書ãã¨ãã¯Thenableãªæ„Ÿã˜ã§æ›¸ã„ã¦ã‚‹ã“ã¨ãŒå¤šã„。 Thenableã£ã¦ã®ã¯ã©ã†ã„ã†ã“ã¨ã‹ã¨ã„ã†ã¨ã€typescirptã®es6-promises ã§ã¯æ¬¡ã®ã‚ˆã†ã«å®šç¾©ã—ã¦ã‚る。 interface Thenable<R> { then<U>(onFulfilled: (value: R) => Thenable<U>, onRejected: (error: any) => Thenable<U>): Thenable<U>; then<U>(onFulfilled: (value: R) => Thenable<U>, onRejected?: (error: any) => U): Thenable<U>; then<U>(onFulfilled: (value: R) => U, onRejected: (error: any) => Thenab
Node.js ã«ãŠã‘ã‚‹ Promise を使ã£ãŸä¾‹å¤–å‡¦ç† - from scratch
ã•ã¦ã€ Node.js ã®ã‚¨ãƒ©ãƒ¼ãƒãƒ³ãƒ‰ãƒªãƒ³ã‚°ã¯é›£ã—ã„ã¨è¨€ã‚ã‚Œã¦ã¾ã™ãŒã€ 2016å¹´ç¾åœ¨ã€ã¤ã¾ã‚ŠNodeã® v4 ã¨ã‹ v6 ãŒä¸»æµã«ãªã‚Šã€ Promise ãŒåŸºæœ¬çš„ãªå‡¦ç†ã¨ã—ã¦æŽ¡ç”¨ã•ã‚Œã¦ã„る状æ³ã§ã¯ã©ã†ã§ã—ょã†ã‹ã€‚ã¡ã‚‡ã£ã¨è€ƒãˆã¦ã¿ã¾ã™ã€‚ 一応ã“ã‚Œã®è£œè¶³ã§ã™ã€‚ qiita.com TL;DR 未ã ã«é›£ã—ã„。ãŸã ã—〠Promise ã§æ”¹å–„ã•ã‚Œã¦ã„る。async-await ã‚„ zone ã¾ã§æ¥ãŸã‚‰ã‹ãªã‚Šæ¥½ã«ãªã‚‹ã€‚ ã‚ã¨ã€ unhandledRejection ㌠uncaughtException よりも酷ã„ã“ã¨ã«ãªã‚‰ãªã„ã®ã§ã€å¤§åˆ†ãƒžã‚·ã«ãªã£ã¦ã„る。 Node.js ã®ã‚¨ãƒ©ãƒ¼ãƒãƒ³ãƒ‰ãƒªãƒ³ã‚°ã®é›£ã—ã• ã¾ãš JavaScript ã«ã¯åŒæœŸã¨éžåŒæœŸã®ã‚¨ãƒ©ãƒ¼ãƒãƒ³ãƒ‰ãƒªãƒ³ã‚°ã®ã‚„ã‚Šæ–¹ãŒã‚ã‚Šã¾ã™ã€‚å‰è€…ã¯æ‰€è¬‚ try-catch ã«ã‚ˆã‚‹æ–¹æ³•ã€å¾Œè€…㯠callback を使ã£ã¦ç¬¬ä¸€å¼•æ•°ã§å®Ÿç¾ã™ã‚‹æ–¹æ³•ã‚„ emit(
Promise Cancellation Is Dead — Long Live Promise Cancellation!
Promise Cancellation Is Dead — Long Live Promise Cancellation! Not very long ago Domenic Denicola (worth a follow, a very smart guy) withdrew his proposal for promise cancellation from the TC39. A lot of people might think that means that promise cancellation isn’t coming to JavaScript. Those people would be right, if you couldn’t already cancel a promise via very similar means to what was propose
Promiseã¯ã©ã†å‹•ä½œã™ã‚‹ã®ã‹ – Promiseを実装ã—ã¦ã¿ã‚‹ | POSTD
目次 1. ã¯ã˜ã‚ã« 2. Promiseã®æ¦‚念をç†è§£ã™ã‚‹ 幕間：行列ãŒå«Œã„ãªå¥³ã®å 2.1 Promiseã¨ã¯ä½•ã‹ï¼Ÿ å¹•é–“ï¼šå®Ÿè¡Œé †åº 2.2 Promiseã¨ä¸¦è¡Œå‡¦ç† 幕間：å¼ã®æŠ½è±¡åŒ– 3. Promiseã®ã‹ã‚‰ãã‚Šã‚’ç†è§£ã™ã‚‹ 3.1. Promiseã§å¼ã‚’é †åºä»˜ã‘ã™ã‚‹ 3.2. 最å°é™ã®Promise実行 4.Promiseã¨ã‚¨ãƒ©ãƒ¼å‡¦ç† 幕間：計算失敗ã®å ´åˆ 4.1. エラーをPromiseã§å‡¦ç†ã™ã‚‹ 4.2. Promiseã®å¤±æ•—ã®ä¼æ’ 5. Promiseã®çµåˆ 5.1. Promiseを確定的ã«çµåˆã™ã‚‹ 5.2. Promiseã‚’éžç¢ºå®šçš„ã«çµåˆã™ã‚‹ 6. Promiseã®å®Ÿç”¨çš„ãªç†è§£ 6.1. ECMAScript Promiseã®å°Žå…¥ 6.2. .then ã®åˆ†æž 7. Promiseã¨ã¯ç›¸æ€§ãŒæ‚ªã„ケースã¨ã¯ï¼Ÿ 8. ã¾ã¨ã‚ å‚考文献 è¿½åŠ è³‡æ–™ 資料ã¨ãƒ©ã‚¤ãƒ–ラリ 1. ã¯ã˜ã‚ã«
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