[cannabis_sam]

Regarding 2. How are comptime values restricted to total computations? Is it just by the fact that the compiler actually finished, or are there any restrictions on comptime evaluations?

[mppm]

Yes, comptime evaluation is restricted to a configurable number of back-branches. 1000 by default, I think.

[pron]

They don't need to be restricted to total computation to be referentially transparent. Non-termination is also a reference.