Perhaps better restore than enable interrupts:   int main() {     interrupts_lock lock;     {         interrupts_lock lock;         critical_section<lock>();     }     critical_section<lock>(); } interrupts disabled interrupts disabled critical section interrupts enabled critical section // outer critical section runs with enabled interrupts interrupts enabled -----Ursprüngliche Nachricht----- Von: Ell via Std-Proposals <std-proposals_at_[hidden]> Gesendet: Fr 13.02.2026 17:05 Betreff: Re: [std-proposals] Canonical State Enforcement An: std-proposals_at_[hidden]; CC: Ell <ell.ell.se_at_[hidden]>; On Friday, February 13th, 2026 at 12:44 PM, David Brown via Std-Proposals <std-proposals_at_[hidden]> wrote: > > > On 13/02/2026 10:14, Simon Schröder via Std-Proposals wrote: > > > > Probably not the most elegant solution, but providing the tag as > > template parameter would have zero runtime-overhead. > > > > Yes, I have thought a lot about that. > > But what is missing there is that there is no way to control the use of > a type. > > If we have a type "irq_disabled" with no public destructor, then the > only way I can get a member of that type and pass it on to a restricted > function is : > > irq_disabled irqs_off = disable_interrupts(); > modify_interrupt_table(irqs_off, new_interrupt_vector); > > > With a template, you can write : > > using irqs_off = irq_disabled; > modify_interrupt_table<irqs_off>(new_interrupt_vector); > > At no point are you forced to remember to call "disable_interrupts()". > You might as well just encode the requirement in the function name > (which is a well-established technique, but I hope to do better) : > > modify_interrupt_table_with_irqs_off(new_interrupt_vector); > > > Even with non-type template parameters rather than type parameters, you > can't (AFAICS) enforce the correct usage here. You can do something like this: https://godbolt.org/z/5q3z33nve It's hard to use that to revoke permissions instead of grant permissions though. -- Std-Proposals mailing list Std-Proposals_at_[hidden] https://lists.isocpp.org/mailman/listinfo.cgi/std-proposals