[dralley]

Session types. Managing hardware state via the type itself, such that it is not possible to create code that does something with (e.g. an IO pin) unless it has first been properly set up, and it's guaranteed at compile time with no runtime checks.

Guarding against mutable aliasing with respect to hardware state could be enormously valuable.

[gmueckl]

How is a solution using a session type different from what you get with a C++ object with a constructor?

I don't quite understand what you are saying in your second paragraph.