static foreach considered

[rsw0x via Digitalmars-d]

On Tuesday, 9 June 2015 at 00:01:07 UTC, Idan Arye wrote:
> On Monday, 8 June 2015 at 22:15:32 UTC, rsw0x wrote:
>> On Monday, 8 June 2015 at 20:02:11 UTC, Andrei Alexandrescu 
>> wrote:
>>> I'm trying to collect together motivating examples and to 
>>> figure out the semantics of the feature.
>>
>> maybe not completely related, but I made a blog post on using 
>> CTFE to unroll foreach at compiletime
>>
>> https://rsw0x.github.io/post/switch-unrolling/
>>
>> I find myself often writing recursive templates for 
>> compile-time generation of constructs that could be done 
>> cleaner with static foreach.
>
> I also use this method alot, and sometimes encounter this 
> "bug": http://dpaste.dzfl.pl/16af3c5dad73
>
> The break inside the `foreach` is breaking from the `foreach`, 
> not from the `switch`, so it continues to execute the `default` 
> clause.
>
> This is not really a bug - `foreach` unrolling is more of a 
> loop unrolling optimization that we hijack, so it makes sense 
> `break` inside it will act like it's inside a regular 
> `foreach`. With `static foreach`, we might want `break`(and 
> `continue`) to operate on the containing, runtime control 
> structure.

I knew there was something I was forgetting in that short 
example, thanks for the reminder.

Interestingly, the assembly generated with `break` and `break 
label` with a label on the switch is exactly the same. I don't 
have time right now to go review the spec, so I have no idea if 
that's correct.