Re:Why the New V8 Is So Damn Fast
by axilmar on Tuesday July 31, 2018 @05:06AM
(#17651630)
Why does it have to be that the order of members matters? shouldn't both {x,y,z} and {z,x,y} compile down to {x,y,z}?
[ Parent
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In JS for-in loop enumerates keys in the insert order. So {x,y,z} is different from {z,x,y}
AFAIK, that's not true; the spec doesn't guarantee that it iterates in insertion order, it's just how it's commonly implemented in browsers.
Nope, they should be iterated in their defined order: https://tc39.github.io/ecma262/#sec-ordinaryownpropertykeys
I think they added this with ES2015.