Does JSON Preserve the Order of Elements in Lists?

Preservation of Order in JSON Lists

While JSON objects may not inherently preserve the order of their elements, the order of elements in JSON lists, also known as arrays, is indeed maintained.

This behavior is explicitly defined in RFC 7159, which specifies the JSON data interchange format:

"An array is an ordered sequence of zero or more values."

Some implementations may extend this behavior to JSON objects as well, preserving the order of name/value pairs. However, this is not a guaranteed feature.

Therefore, in JSON, the order of elements within lists is considered significant and will be retained. This is particularly useful when the order of items is crucial to the data's interpretation, such as when working with ordered sequences of values.

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