And-in-sequence
From FreeSpace Wiki
And in sequence (Boolean operator) Returns true if all of its arguments have become true in the order they are listed in. NOTE 1: This is more strict than might be apparent. If argument 2 becomes true while argument 1 is still pending, then the operator will immediately return false because the arguments did not become true in the correct sequence. NOTE 2: This operator should not be used with when-argument or any -argument SEXPs because its method of caching arguments is not compatible. Returns a boolean value. Takes 2 or more boolean arguments.
Notes
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