Rob Palmer

TypeScript 7.1 Beta is out 🎉 🔶 Import Attributes 🔶 Source Phase Imports 🔶 Types: es2026 🔶 Types: Promise.allKeyed, Iterator.zipKeyed 🔶 Types: Iterator chunks/join/includes 🔷 An API for tooling ✨ 🔷 tsconfig: Content Mappers 🔷 Perf: 1.2-1.9x faster, 15-50% less memory

TypeScript excitement 😉 tsrs is a fast TypeScript compiler by Max Schwenk that is now maintained by VoidZero 🎉 The Cloudflare blog post states that the features and behavior will be determined only by the TypeScript team to avoid fragmenting the language 👍

This is cool. JS minifier Terser v5.50 added experimental support for erasable TypeScript 👻 It corresponds to TypeScript’s erasableSyntaxOnly flag. Node.js & ts-blank-space also use this. github.com/terser/terse...

ECMAScript excitement 😉 This week @tc39.es advanced these proposals 🎉 4️⃣ Dynamic Code Brand Checks 4️⃣ Iterator Chunking/Includes/Join 3️⃣ Thenable Curtailment 2️⃣.7️⃣ default in export * from "mod" 2️⃣.7️⃣ export defer 2️⃣.7️⃣ JSON.parse options 2️⃣ BigInt from Exponential 2️⃣ Composites 1️⃣ Pulling in AbortController

bsky.app/profile/robp...

ECMAScript excitement 😉 This week @tc39.es advanced these proposals 🎉 4️⃣ Dynamic Code Brand Checks 4️⃣ Iterator Chunking/Includes/Join 3️⃣ Thenable Curtailment 2️⃣.7️⃣ default in export * from "mod" 2️⃣.7️⃣ export defer 2️⃣.7️⃣ JSON.parse options 2️⃣ BigInt from Exponential 2️⃣ Composites 1️⃣ Pulling in AbortController

bsky.app/profile/robp...

ECMAScript excitement 😉 This week @tc39.es advanced these proposals 🎉 4️⃣ Dynamic Code Brand Checks 4️⃣ Iterator Chunking/Includes/Join 3️⃣ Thenable Curtailment 2️⃣.7️⃣ default in export * from "mod" 2️⃣.7️⃣ export defer 2️⃣.7️⃣ JSON.parse options 2️⃣ BigInt from Exponential 2️⃣ Composites 1️⃣ Pulling in AbortController

bsky.app/profile/robp...

ECMAScript excitement 😉 This week @tc39.es advanced these proposals 🎉 4️⃣ Dynamic Code Brand Checks 4️⃣ Iterator Chunking/Includes/Join 3️⃣ Thenable Curtailment 2️⃣.7️⃣ default in export * from "mod" 2️⃣.7️⃣ export defer 2️⃣.7️⃣ JSON.parse options 2️⃣ BigInt from Exponential 2️⃣ Composites 1️⃣ Pulling in AbortController

The full agenda including links to the slides and presentation materials can be found here. Full meeting notes will be published in roughly two weeks time. github.com/tc39/agendas...

ECMAScript excitement 😉 This week @tc39.es advanced these proposals 🎉 4️⃣ Dynamic Code Brand Checks 4️⃣ Iterator Chunking/Includes/Join 3️⃣ Thenable Curtailment 2️⃣.7️⃣ default in export * from "mod" 2️⃣.7️⃣ export defer 2️⃣.7️⃣ JSON.parse options 2️⃣ BigInt from Exponential 2️⃣ Composites 1️⃣ Pulling in AbortController

ECMAScript excitement 😉 Congrats to @nicr.dev on advancing "Include default export in export * from" to Stage 2.7 at @tc39.es today 🎉 Today re-exporting the contents of another module omits the default export. It is believed this behavior change is web-compatible.

Slides docs.google.com/presentation...

ECMAScript excitement 😉 Congrats to @ashley-c.bsky.social from TechAtBloomberg on advancing the Composites proposal to Stage 2 at @tc39.es today 🎉 Composites are objects that are compared by value instead of identity. They are an evolution of Record & Tuple proposal.

These slides were presented today. docs.google.com/presentation...

ECMAScript excitement 😉 Congrats to @nicr.dev on advancing `export defer` to Stage 2.7 at @tc39.es today 🎉 It is a performance feature that permits lazy evaluation of re-exported bindings. It is useful for reducing the cost of partially-used barrel files 👍

Proposal repo: github.com/tc39/proposa...

ECMAScript excitement 😉 Congrats to Richard Gibson on advancing BigInt from Exponential to Stage 2 at @tc39.es today 🎉 🔶 BigInt("1e2") It allows a BigInt to be created from a number that includes an exponential component 👍

Slides: docs.google.com/presentation...

ECMAScript excitement 😉 Congrats to @peet.bsky.social from TechAtBloomberg advancing JSON.parse Options to Stage 2.7 at @TC39 today 🎉 There are two independent opt-ins. 🔶 deep freezing the entire object 🔶 non-array objects get a null prototype Names may change ⚠️

Slides presented today docs.google.com/presentation...

ECMAScript excitement 😉 Congrats to @michael.ficarra.me on advancing the Iterator Chunking proposal to Stage 4 at @tc39.es today 🎉 It can make iterators that chunk & window content. [0,1,2,3].values().chunks(2); // [0,1], [2,3] [0,1,2,3].values().windows(2); // [0,1], [1,2], [2,3]