What is the point of nothrow?

[Dave Jones]

On Monday, 11 June 2018 at 00:47:27 UTC, Jonathan M Davis wrote:
> On Sunday, June 10, 2018 23:59:17 Bauss via Digitalmars-d-learn 
> wrote:
>> What is the point of nothrow if it can only detect when 
>> Exception is thrown and not when Error is thrown?
>>
>> It seems like the attribute is useless because you can't 
>> really use it as protection to write bugless, safe code since 
>> the nasty bugs will pass by just fine.
>>
>> I'm aware that it's a feature that nothrow can throw Error, 
>> but it makes the attribute completely useless because you 
>> basically have no safety to guard against writing code that 
>> throws Error.
>>
>> To an extend @safe works, but there are tons of stuff that 
>> throws Error which you can only detect and guard against 
>> manually.
>>
>> So what is the point of nothrow when it can only detect 
>> exceptions you'd catch anyway.
>>
>> To me it would be so much more useful if you could detect code 
>> that could possibly throw Error.
>
> Why do you care about detecting code that can throw an Error? 
> Errors are supposed to kill the program, not get caught. As 
> such, why does it matter if it can throw an Error?
>
> Now, personally, I'm increasingly of the opinion that the fact 
> that we have Errors is kind of dumb given that if it's going to 
> kill the program, and it's not safe to do clean-up at that 
> point, because the program is in an invalid state, then why not 
> just print the message and stack trace right there and then 
> kill the program instead of throwing anything? But 
> unforntunately, that's not what happens, which does put things 
> in the weird state where code can catch an Error even though it 
> shouldn't be doing that.

It certainly threw (hardehar) me when a failed assert was 
terminating my program without telling me why. I don't know if 
it's just because it was happening in an OS callback function, 
but it was definitely a WTF.

So the only solution I could figure is to catch throwable in the 
callback function, dump the message, and then PostQuitMessage(0). 
It just seems retarded that Throwables can still happen in a 
nothrow function.