explicitly temporary or permanent alias

[Richard (Rikki) Andrew Cattermole]

On 13/10/2024 7:47 AM, monkyyy wrote:
> Alias reassignment has various bugs, including regressions, in an 
> attempt to optimize it. Sometimes I want a symbol to survive, other time 
> I(by which i mean core devs) want it deleted and hoping a redesign to a 
> static foreach improves compile times.
> 
> I expect it will be years before its nailed down and correct.
> 
> I suggest two new traits `__traits(delete_alias)` and 
> `__traits(keep_alias)`, that explicitly keep or delete aliases a work 
> arounds
> 
> ```d
> alias bar=Seq!();
> static foreach(...){
>    ...//something that triggers bugs
> }
> bar=__traits(delete_alias);//marks bar for deletion
> ```
> 
> ```d
> alias bar=Seq!();
> bar=__traits(keep_alias);//turn off optimizations
> static foreach(...){
>    ...//something that triggers bugs
> }
> foo=bar;//foo should be correct now
> ```

If we were to do something like this, it would be a pragma as a hint 
instead.

That doesn't need a DIP as it is a compiler specific instruction.

Needs a bug report, with behavior of what you want done.

Given its tuning related of existing behavior, you may have some success 
doing a PR for it.