How to tell if session loaded?

I don't believe the $_SESSION variable is available until the session has been initiated, IIRC. So you could do isset($_SESSION).

Or you could not worry about checking, since as long as you use the session() helper method, it will be automatically started on the first use. Trying to grab a variable like with $key = session('some_key') will ensure the session is started before grabbing the value.

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