Everybody knows that you can retrieve an ActiveRecord object like this:
user = User.find(41) => #<User id: 41>
But did you know that you can pass multiple ids to the find method?
user = User.find(1, 2, 5) => [#<User id: 1>, #<User id: 2>, #<User id: 5>]
Principle of least surprise.
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