[Pre-RFC] Single function call `unsafe`

[scottmcm]

@kornel

I would prefer unsafe blocks to be larger to cover all of these concerns together, because the entire context must be checked for safety.

Agreed. What I want help with is making sure I satisfied all the preconditions, not just knowing which things have preconditions.

I'll re-use this previous post about it:

Pre-RFC: Unsafe reasons

TBH, I think needing them in the middle of the call like that will defacto result in people being unwilling to actually list out the reasons in nice separable ways, because it'll just be so ugly to see them all through the middle of the logic. I do like the direction of having to meet all the requirements -- not just the ones you remembered -- but think it should work differently so while you still need to cover them, you don't need to repeat them endlessly. For example, I think of code like …

(If we can write proofs of predicates, then all these individual unsafes become unnecessary.)