React Native / Expo: 'defineProperty' error persists in TypeBox 1.0.x

[feunard]

Hello,

It seems we still have an issue with TypeBox and Expo / Metro bundler.

• Expo SDK 54 (React Native 0.81)
• Metro bundler with Babel
• TypeBox 1.0.71

Reproduction Steps

npx create-expo-app@latest my-app
cd my-app
npm install typebox

Add import in app/(tabs)/index.tsx:

import 'typebox'

Run:

npm run ios

Error

ERROR  [TypeError: Cannot read property 'defineProperty' of undefined]

Root Cause

In src/type/types/object.ts:

export var Object = _Object_

Metro + Babel transforms this in a way that shadows the global Object, breaking Object.defineProperty calls.

Potential Fix

Replace the line with:

export { _Object_ as Object }

Related Issues

• Expo/RN: Cannot read property `defineProperty' of undefined #1256
• React Native Support #1454

Thanks for looking into this!

[sinclairzx81]

@feunard Hi, thanks for reporting

It seems we still have an issue with TypeBox and Expo / Metro bundler.

Ah, I keep thinking I've resolved this issue, but this issue keeps coming back! Thanks for the repro here though. Just bear in mind I'm not a react-native developer and don't do much mobile development (or own a ios device), but was able to reproduce the error running the following.

$ npx create-expo-app@latest my-app
$ cd my-app
$ npm install typebox

# Add import in app/(tabs)/index.tsx:

$ npm run web # ERROR  [TypeError: Cannot read property 'defineProperty' of undefined]

I have just published version 1.0.72 which updates the export to use export-alias as per your suggestion. This seems to fix the error when compiling for the web target and "should" resolve it for the ios target if it uses the same bundling infrastructure.

export { _Object_ as Object }

Related PR here.

#1503

---

Will close this one out for now as this should have fixed the issue, but if you run into any problems, feel free to ping on this thread. And again, thanks for the repro.
Cheers
S

[feunard]

It's working now, thank you for the quick fix :D