static foreach considered

[Timon Gehr via Digitalmars-d]

On 06/08/2015 10:16 PM, Idan Arye wrote:
> On Monday, 8 June 2015 at 20:02:11 UTC, Andrei Alexandrescu wrote:
>> Walter and I are looking at ways to implement it. Here's a baseline
>> without static foreach - a "trace" function that prints function calls
>> before they are made:
>>
>> http://dpaste.dzfl.pl/762c83c7fe30
>>
>> If the function is overloaded, that won't work. In such cases, static
>> foreach might be helpful. Here's code from the cycle "I have a dream":
>>
>> http://dpaste.dzfl.pl/82a70c809210
>>
>> I'm trying to collect together motivating examples and to figure out
>> the semantics of the feature.
>>
>>
>> Andrei
>
> How will scoping work? Similar to mixin templates?
> ...

I think the body should have access to a scope that is hidden from the 
outside which contains the loop variable, but declarations should be 
inserted into the enclosing scope like for static if.

> It would be nice together with this feature to be able to mixin
> identifiers:
>
>      static foreach (ident; ["foo", "bar"])
>      {
>          auto mixin(ident)()
>          {
>              // code for foo/bar
>          }
>      }
>
> Otherwise, other than overloads and template instantiations this won't
> be much better then generating code strings with CTFE...

+1. Other use cases:

auto mixin(ident) = x;

identifier.list.mixin(ident).foo();

import std.mixin(ident);