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  • Deterministic enumeration

Deterministic enumeration

# David Bruant (12 years ago)

I've seen a bug report on Firefox [1] and was wondering whether deterministic property enumeration [2] was still on the table for ES6.

Thanks,

David

[1] bugzilla.mozilla.org/show_bug.cgi?id=865760 [2] strawman:enumeration

# Brendan Eich (12 years ago)

David Bruant wrote:

Hi,

I've seen a bug report on Firefox [1] and was wondering whether deterministic property enumeration [2] was still on the table for ES6.

My comment from that bug:

bugzilla.mozilla.org/show_bug.cgi?id=865760#c5

Ignoring the SpiderMonkey threshold, we do have strawman:enumeration. It was not promoted to harmony:proposals status for ES6. It's a bit late to jam in, but implementations along with that strawman should try to converge. I doubt the threshold will find consensus.

There's a long V8 issue on enumeration not using insertion order: code.google.com/p/v8/issues/detail?id=164 I believe. Closed: WorkingAsIntended, still drawing fire from developers.

# Aymeric Vitte (12 years ago)

I don't know what is a determinist way for enumeration and who is right (I would be more enclined to keep the chronological order of property settings but if the strawman says the contrary there must be a good reason), but not knowing about #164, I wrote one day : code.google.com/p/v8/issues/detail?id=2353

This was closed about 2s after I wrote it, but here what is not determinist at all is that the enumeration order can change depending on what you are doing.