Typed Programs Don't Leak Data
&gt; This is safe because whoever has access to the more private data would also have access to the public one.<p>I think in real world scenarios, this would not be true of most stakeholder requirements.<p>That&#x27;s what actually confused me here, because I don&#x27;t see the use case in having levels of privacy.<p>I can see value in a boolean private&#x2F;not private, for security, where private data you&#x27;d expect to always be access logged, stored securely (encrypted), transfered over secure channels, etc. And you wouldn&#x27;t ever want this data to accidentally be leaked and end up stored&#x2F;exchanged in a non-secure place (like unencrypted app logs).<p>But for privacy, I feel that you&#x27;d want to tie the data to some permission control of some sort, and levels don&#x27;t make sense for it. You&#x27;d want something like &quot;user making request&quot;, and I don&#x27;t know if you can embed that in types and check things statically, since it very much seems like a runtime thing.