explicit castable to bool for predicate restraints?

[monarch_dodra]

On Monday, 17 December 2012 at 23:40:19 UTC, Jonathan M Davis 
wrote:
> On Monday, December 17, 2012 10:23:45 monarch_dodra wrote:
>> Opinions? Just want to know how which direction to take my 
>> future
>> developments.
>
> How about we just require that they all return bool? I see no 
> reason to
> support anything else.
>
> - Jonathan M Davis

That seems excessive to me. I think a lot of predicates, 
especially if they have C linkage, will return a (u)int whose 
values are just 0 or 1. I see no reason to not support this.