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digitalmars.D.learn - Doing a `static foreach` or `foreach` through enum members in a

reply Liam McGillivray <yoshi.pit.link.mario gmail.com> writes:
I know that DStep generates CTFE functions to automatically make 
aliases for enum members so that the can be used without the enum 
name, as is done in C. DStep does it with a CTFE function, though 
it should also be possible with a mixin template.

Here is my attempt so far, using a mixin template:
```
template enumMixin(Enum) {
     private import std.traits;
     static foreach(member; EnumMembers!Enum) static if 
(__traits(isDeprecated, member))
     {
         private alias m = __traits(identifier, member);
         alias m = member;
     }
};
```

It hasn't worked so far.
Apr 19
parent reply Liam McGillivray <yoshi.pit.link.mario gmail.com> writes:
Well, someone on the Discord server has been helping me attempt 
this, but while I managed to get a solution that compiles without 
errors, I still get the deprecation warning.

Here is what I ended up with:
```
template enumMixin(alias Enum) {
     static foreach(m; __traits(allMembers, Enum)) static if 
(!__traits(isDeprecated, __traits(getMember, Enum, m)))
     {
         mixin("alias "~m~" = __traits(getMember, Enum, m);");
     }
};
```

Unfortunately, the deprecation warnings still appear if the enum 
contains any deprecated members. I'm starting to suspect that the 
language doesn't currently have any features to stop this from 
happening. This is unfortunate, as it *should* be possible to 
process an enum with deprecated members *without* getting these 
warnings.
Apr 19
parent Liam McGillivray <yoshi.pit.link.mario gmail.com> writes:
On Friday, 19 April 2024 at 22:24:17 UTC, Liam McGillivray wrote:

 ```
 template enumMixin(alias Enum) {
     static foreach(m; __traits(allMembers, Enum)) static if 
 (!__traits(isDeprecated, __traits(getMember, Enum, m)))
     {
         mixin("alias "~m~" = __traits(getMember, Enum, m);");
     }
 };
 ```


Correction: The code shown above actually *does* work properly 
without any deprecation warnings. I made a mistake with the enum 
being set to the CTFE function I was previously using instead of 
this template. This template actually works.

I posted here for visibility and searchability, in case anyone 
else wants to do something like this.
Apr 19