syntax - What's the difference between [[]] and [] in Ruby? -

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came across snippet :

@@datalist[i] = [[0,[]]]

what double brackets do? if wrote :

@@datalist[i] = [0,[]]

.. work different?

[] empty array.

[[]] array containing empty array single element.

[0,[]] array containing 2 elements.

[[0, []]] array containing 1 element, happens array.


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