forcing weak purity

[Alex Rønne Petersen]

On 23-05-2012 13:48, Artur Skawina wrote:
> On 05/23/12 05:22, Steven Schveighoffer wrote:
>> it has no parameters and no return, marking it as pure makes it strong pure, and an optimizing compiler can effectively remove the call completely!
>
> Arguably a pure function not returning a value doesn't make sense... D's definition
> of "pure" makes things a bit more complicated, and the fact that it is so vaguely
> defined doesn't help. Eg what does "a pure function can terminate the program" mean?
> A literal interpretation forbids eliminating any calls, or even moving them in a way
> that could affect control flow (by terminating early/late)...
>
> Anyway, result-less "pure" functions obviously can have side effects, so removing
> calls to them shouldn't be allowed.
>
>
> On 05/23/12 05:31, Alex Rønne Petersen wrote:
>> I'm in favor of what you suggested on GitHub: A @weak attribute to enforce weak purity for functions marked pure.
>
> No. "@weak" should be for defining weak symbols, reusing it for anything else would
> just cause confusion,
>
> artur

I had no idea what weak symbols were until I read your post. Just due to 
that fact, I am not convinced that weak symbols are interesting enough 
to occupy @weak.

-- 
Alex Rønne Petersen
alex at lycus.org
http://lycus.org