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for-in order

for stage 4

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github.com/tc39/proposal-for-in-order

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Recap

  • Reflect.ownKeys is ordered
  • for (a in b) {...} is not

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Proposal

Make for-in ordered in

the common case.

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This also affects Object.keys, JSON.stringify, etc.

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Proposal:

​

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Pull Request: tc39/ecma262#1791

Tests: tc39/test262#2432

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Stage 4?