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Discussion on: Using JavaScript Symbol.toStringTag for objects types description

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aminnairi profile image
Amin • Edited
type User = { name: string }
const user = { name: 'john' }

Object.defineProperty(user, "name", {
  value: undefined
});

alert(user.name.length); // Cannot read property 'length' of undefined (in JavaScript after transpilation)
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This compiles just fine in TypeScript and even gives an error in the playground when run.

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ninofiliu profile image
Nino Filiu

Sure, but come on, that's just deliberately trying to deceive TypeScript at this point ^^