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#4546 — Order of properties falsely described as implementation-specific

• bug_id: 4546
• creation_ts: 2015-11-21 11:35:00 -0800
• short_desc: Order of properties falsely described as implementation-specific
• delta_ts: 2015-11-21 11:46:26 -0800
• product: ECMA-262 Edition 6
• component: technical issues
• version: unspecified
• rep_platform: All
• op_sys: All
• bug_status: CONFIRMED
• priority: Normal
• bug_severity: enhancement
• everconfirmed: true
• reporter: Axel Rauschmayer
• assigned_to: Allen Wirfs-Brock

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• commentid: 14897
• comment_count: 0
• who: Axel Rauschmayer
• bug_when: 2015-11-21 11:35:04 -0800

http://www.ecma-international.org/ecma-262/6.0/#sec-object.keys

“If an implementation defines a specific order of enumeration for the for-in statement, the same order must be used for the elements of the array returned in step 4.”

AFAICT, this is wrong on two accounts:

1. It’s not a question of “if an implementation defines a specific order” – it is defined for all implementations, by the spec.
2. The order doesn’t depend on for-in, it depends on [[OwnPropertyKeys]].

A note for EnumerableOwnNames [1] also misstates a dependency on for-in (similarly to #2 above):

“The order of elements in the returned list is the same as the enumeration order that is used by a for-in statement.”

[1] http://www.ecma-international.org/ecma-262/6.0/#sec-enumerableownnames


Am I making sense?

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• commentid: 14900
• comment_count: 1
• who: Axel Rauschmayer
• bug_when: 2015-11-21 11:46:26 -0800

*** Bug 4547 has been marked as a duplicate of this bug. ***