Order of Storing/Enumerating Keys in a JS Object
14.07.2021

In JS, objects were 'unordered' until ES5. Starting from ES6, there is a predictable order of iterating through an object's properties.

1. All non-negative integer keys less than 2^32, in ascending order. (e.g., '1', '79', etc.). Typically, all valid array indexes. (non-negative numbers up to 2^32)

  Warning: '05' will not be considered an integer key, as the integer parsed from it yields a different string representation.

2. All string keys in the order of insertion (in the order they were added to the object).

  Here, numeric strings not falling within the first step and floating-point numbers will be covered.

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