On Oct 27, 2014, at 8:35 AM, Domenic Denicola wrote:

> From: es-discuss [mailto:es-discuss-bounces at mozilla.org] On Behalf Of Adam Klein
> 
>> For what it's worth, given that there exists one implementation (IE 11) that gets this right per spec, I'm more inclined as an implementor to match that than to try to get the spec changed here.
> 
> Eh, but then we have two implementations agreeing, which is the road toward locking in this behavior. Better to take advantage of the interoperability wasteland out at the 2^32 - 1 frontier, and seize the day by making even more daring changes like pushing the boundaries to 2^53 - 1!!

The reason Array's max length wasn't increased to 2^53 - 1 relates to legacy array wrap-around behavior t the the 2^32 - 1 limit.  Nobody wanted to risk changing that because of potential web compat. issues.

Allen

On Oct 27, 2014, at 8:35 AM, Domenic Denicola wrote:

> Eh, but then we have two implementations agreeing, which is the road toward locking in this behavior. Better to take advantage of the interoperability wasteland out at the 2^32 - 1 frontier, and seize the day by making even more daring changes like pushing the boundaries to 2^53 - 1!!

The reason Array's max length wasn't increased to 2^53 - 1 relates to legacy array wrap-around behavior t the the 2^32 - 1 limit.  Nobody wanted to risk changing that because of potential web compat. issues.