CT foreaches

[Nick Treleaven]

On Friday, 1 August 2025 at 15:47:47 UTC, monkyyy wrote:
> On Friday, 1 August 2025 at 15:15:35 UTC, Nick Treleaven wrote:
>> 
>> Up to here is all as expected, right?
>
> No, `foreach(alias` is functionally undocumented

Thanks, fix:
https://github.com/dlang/dlang.org/pull/4279

>>> 	pragma(msg,"---");
>>> 	foreach(enum i;0..3){// ERROR ISNT CT. ISNT AN ENUM
>>> 		pragma(msg, i.stringof);
>>> 		//foo!i; //doesnt compile
>>
>> You're using runtime foreach here. It's only expanded at 
>> compile-time when the aggregate is a sequence - as the spec 
>> says.
>>
>
> `foreach(enum i;0..3){` is directly from the dip 1010 its

That's under the 'Limitations of this DIP / possible future 
improvements' section:
https://github.com/dlang/DIPs/blob/master/DIPs/accepted/DIP1010.md#allowing-alias-and-enum-on-regular-foreach-loop-variables

> unclear from the responce if it was accepted or rejected

That DIP says 'Status: 	Accepted' at the top.

>>> b) enum or alias of aliasSeq, whoever made thought there be 
>>> an upgrade to fully generalize the syntax
>>
>> Not sure what you mean for (b).
>
> dip 1010 was optimistic about near term upgrades to static 
> foreach; static break and continue
>
> ---
>
>> The confusing thing is that enum there is silently ignored. I 
>> think we could add an error for that.
>
> That would be a breaking change now, most code swapped from 
> runtime to ct should continue working tho, better to just 
> implement it

Not really, no one should have used enum/alias with a non-static 
ForeachRangeStatement because (as you pointed out), it wasn't in 
the spec. If they did use it, they'd probably realize that those 
storage classes had no effect.