Comment #97 on issue 164 by mendesjuan: Wrong order in Object properties
interation
http://code.google.com/p/v8/issues/detail?id=164
Let me chime in also since everybody's throwing their two cents in the fire.
I wish Chrome would keep the order of iteration for properties as they were
added. Throughout browser history, browsers have mimicked existing
de-facto standards even if they weren't in the actual standards. Having
said that, I'm glad I made a conscious decision not to rely on
that 'feature' when I first noticed it specifically because of things like
this.
I always use arrays when I need to rely on order. If I also need quick
access to objects by a key, I run the array through the following method to
create a map keyed by specific property
/**
* Given an array and a property name to key by, returns a map that is
keyed by each array element's chosen property
* This method supports nested lists
* Sample input: list = [{a: 1, b:2}, {a:5, b:7}, [{a:8, b:6}, {a:7,
b:7}]]; prop = 'a'
* Sample output: {'1': {a: 1, b:2}, '5': {a:5, b:7}, '8': {a:8,
b:6}, '7':{a:7, b:7}}
* @param {object[]} list of objects to be transformed into a keyed object
* @param {string} keyByProp The name of the property to key by
* @return {object} Map keyed by the given property's values
*/
function mapFromArray (list , keyByProp) {
var map = {};
for (var i=0, item; item = list[i]; i++) {
if (item instanceof Array) {
// Ext.apply just copies all properties from one object to another,
// you'll have to use something else. this is only required to
support nested arrays.
Ext.apply(map, mapFromArray(item, keyByProp));
} else {
map[item[keyByProp]] = item;
}
}
return map;
};
I think the above is better than appending characters to keys from both the
server and client side.
To web devs: future proof your code, don't rely on non-standard behavior.
To Chrome devs, don't be such hard a$$es about keeping an existing behavior
that many are asking for.
--Juan
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