Function that returns a user's role

There are times I would like to show or hide data, allow access, etc. based on the user's role. 

For example, some data is sensitive, and I would like to use Dynamic Cell Access to allow someone with the user role "Admin" to read/write the sensitive information, while someone without the Admin role would see nothing. 

Another use example, I want to allow users with the role of "Project Manager" to edit only their own projects, while others that either don't have the "Project Manager" role, OR who aren't the active project manager, can see the project's information as read only.  

Both of these require that I be able to somehow check they have proper role. Currently I believe the only way is whether they can get to a dashboard, which makes for a lot jumping through hoops to prevent unauthorized access.