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Comparing DateTime Structs In Elixir

Remember, comparisons in Elixir using ==/2, >/2, </2 and friends are structural and based on the DateTime struct fields. For proper comparison between datetimes, use the compare/2 function.

As the DateTime docs say, you’ll want to use compare/2 in order to accurately compare two DateTime structs.

{:ok, older} = DateTime.from_naive(~N[2016-05-24 13:26:08.003], "Etc/UTC")
{:ok, newer} = DateTime.from_naive(~N[2017-11-24 13:26:08.003], "Etc/UTC"), newer)
#=> :lt, older)
#=> :gt, newer)
#=> :eq

When using compare/2, you’ll get one of :lt, :gt, or :eq as a result, meaning less than, greater than, or equal respectively.

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