一部の開発ツールでは「JavaScript」ではなく「ECMAScript」という名称を使わざるを得ません。理由は単純で、JavaScriptの商標をOracleが握っているからです。

Have any .NET devs heard of or used Jint before? I prototyped some ideas years ago with it. Cool to see it still well maintained and all the ECMAScript features supported now.

／ 重版情報📢 ＼ 『いちばんやさしいJavaScriptの教本 第2版 ECMAScript 2017(ES8)対応 人気講師が教えるWebプログラミング入門』（9️⃣刷） 応用できる基礎が身に付く！ ⬇️試し読みはこちら⬇️ https://t.co/A5rL6feUAO

ECMAScript excitement 😉 Congrats to my coworker @acutmore @TechAtBloomberg on advancing Await Dictionary to Stage 2.7 at @TC39 today 🎉 Promise.all returns positional results as an array. Promise.allKeyed allows named results inside an object 👍

ECMAScript 1-3 timeline #jsconfjp

ECMAScript 2026 (the Javascript spec) has a Promise.try() If you pass a sync method to it, it will execute it immediately. It won't schedule it for the next microtask like Promise.resolve.then() does.

With ECMAScript 2026, JavaScript will get more precise about sums, errors, international dates and times — and it may finally be time for Temporal.

UPDATE: There's a 3-character version, and probably the most cursed JavaScript I've ever seen. Shoutout to @bedros_p for finding this one. Has to do with how HTML comments are treated in the ECMAScript spec.

ECMAScript excitement 😉 Congrats to Frank Tang on advancing Intl Locale Info API to Stage 4 at @TC39 today 🎉 It exposes Locale info such as week data (first day in a week, weekend start day, weekend end day), text direction, hour cycles, numbering systems, etc.

PDF版で見ないとわからないECMAScript仕様のページ数、今は834ページもあるのか #jsconfjp

Mediabunny is one of awesome TypeScript/ECMAScript libraries I’ve discovered recently. It’s well-typed, has both simple and easy APIs, and of course perfect use of the (await) using syntax. Wanna add support for m2ts and mmt

ECMAScript excitement 😉 This week TC39 advanced these proposals 🎉 4️⃣ Intl.Locale Info 4️⃣ Iterator.concat 4️⃣ JSON.parse Source Txt 3️⃣ https://t.co/2zSc2BgbUo 2️⃣.7️⃣ Iterator.prototype.join 2️⃣.7️⃣ Promise.allKeyed 2️⃣ Error.captureStackTrace 2️⃣ Import Text 2️⃣ Object.keysLength 🧵

ECMAScript excitement 😉 Congrats to James Snell on advancing Typed Array Find Within to Stage 1 at @TC39 today 🎉 It aims to provide a native indexOf operations for Typed Arrays.

アニメーション制作ソフト friction は、ECMAScript で動きを制御できる。 こういうのがいい。 描画から自力で書こうとしたら大変だけど、位置や大きさ傾きだけスクリプトでいじるのは簡単に書ける。 こういうのでいいんだよ。 https://t.co/FYtstVrC9B

ECMAScript excitement 😉 Congrats to Ruben Bridgewater, @ljharb on advancing Object.keysLength to Stage 2 at @TC39 today 🎉 let count = Object.keysLength(o) It counts string-keyed own properties on an object & avoids the cost of an intermediate array in Object.keys(o).length

We're excited to be hosting the 111th Meeting of @TC39 this week (Nov 18-20)! We welcome the #TC39 delegates to @Bloomberg's office in Tokyo and wish them a truly productive week discussing the future of #ECMAScript / #JavaScript! https://t.co/OPwtIiGfp5 #opensource #JS

@graphite__tech Cause of error: Import is part of ECMAScript module but the browser is treating my JS as CommonScript Solution: Add type="module" to my script tag, i.e. <script type="module" src="{file_location}.js"></script> Code can be found here: https://t.co/1USKhFtaDN

ECMAScript excitement 😉 Congrats to @smooshMap on advancing Joint Iteration to Stage 3 at TC39 today 🎉 It provides synchronized iteration over multiple iterators. 🔸 https://t.co/2zSc2BgbUo vends an array per-iteration 🔸 Iterator.zipToObjects vends an object per-iteration

FYI, ECMAScript directives are StringLiteral according to the ES spec They are just a special kind of string literals (I'm not sure whether directives are a good or bad idea yet, just want to state a fact)