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Andrew Branch
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Andrew Branch
@atcb
Working on TypeScript at Microsoft. I appear when someone says “module resolution” three times in the dark. He/him
Marin, CA
blog.andrewbran.ch
Joined January 2013
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  • user avatar
    Andrew Branch
    @atcb
    Aug 23, 2024
    Editing with @britto_gab's work on region-prioritized diagnostics has been so great: > in our testing on TypeScript’s own checker.ts, a full semantic diagnostics response took 3330ms. In contrast, the response for the first region-based diagnostics response took 143ms! 👏
    user avatar
    TypeScript
    @typescript
    Aug 23, 2024
    The release candidate for TypeScript 5.6 is now available for testing! Give it a try today for more new checks, ways to speed-up your builds, new JS features, and more! devblogs.microsoft.com/typescript/ann…
    3.2K
  • user avatar
    Andrew Branch
    @atcb
    May 27, 2024
    Update for 2024: do whatever you want 🙃
    user avatar
    Christoph Nakazawa
    @cnakazawa
    May 26, 2024
    Do not use `import type` unless you need to.
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    Readers added context
    This comment was written before TypeScript shipped the `verbatimModuleSyntax` configuration option, which improves upon the behavior of `import type`: typescriptlang.org/tsconfig/#verb… Several experts on TypeScript, including the original author of this comment, no longer stand by this guidance: x.com/atcb/status/17… x.com/mattpocockuk/s…
    155K
  • user avatar
    Andrew Branch
    @atcb
    Apr 28, 2024
    This brings up some great questions about a confusing topic, but the advice Brandon found in his research is bad advice! My full explanation via blog post: blog.andrewbran.ch/default-export…
    user avatar
    Brandon McConnell
    Mintlify
    @branmcconnell
    Apr 22, 2024
    Apparently, I've been doing NPM package exports in TSC wrong my entire life. I usually use the ESM `export default _` if I'm doing a default export. This generated CJS output appears to break when require'd in a CJS environment, requiring a property ref of `packageName.default`
    17K
  • user avatar
    Andrew Branch
    @atcb
    Jan 30, 2024
    Touched some rock this weekend 😎
    Me on top of a 40-foot granite rock giving a thumbs up, ready to lower on a climbing rope
    884
  • user avatar
    Andrew Branch
    @atcb
    Jan 19, 2024
    So much exciting stuff landing in TypeScript 5.4! My contribution is very boring, but module nerds like me should know about it. A new setting for bundlers and Bun: "module": "preserve" It implies `--moduleResolution bundler`, which previously only allowed `--module esnext`. 🧵
    17K
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