The scope of the isAuthorized expression is restricted to Perspective sessions. I don’t even think Vision projects utilize Security Levels, and as such the functions serves no purpose in the Vision context.
OK so I just figured something out. I was trying to use isAuthorized in an Expression Tag. It is not available. I guess I should have realized that since tags aren’t specific to either Vision or Perspective.
I created an expression binding in Perspective and was able to use the isAuthorized function.
A little ambiguous but I got it to work. I assumed an expression function was an expression function and should be able to be used in any expression.
If you think about login security in general, and the all-the-time-regardless-of-users nature of gateway tags (all types, not just expression tags), it’ll make more sense. This type of scope-dependence permeates Ignition, so you might consider it first when something doesn’t work the way you assume.