pragma msg field name?

[Chris Katko]

On Tuesday, 27 June 2023 at 04:56:19 UTC, Ali Çehreli wrote:
> On 6/26/23 21:25, Chris Katko wrote:
>
> > How do I get just the field name?
>
> I know .tupleof, which you can typeof() as well:
>
> class myObject{
>     int field1, field2, field3;
>
>     static foreach(field; typeof(this).tupleof)
>     {
>         pragma(msg, field.stringof);
>     }
>
>     static foreach(MemberType; typeof(typeof(this).tupleof)) {
>         pragma(msg, MemberType);
>     }
> }
>
> The output:
>
> field1
> field2
> field3
> int
> int
> int
>
> I had to consult what I wrote years ago:
>
>   http://ddili.org/ders/d.en/tuples.html#ix_tuples..tupleof
>
> Ali

That seems to do the trick, I was really not expecting so much 
text just to get something so simple!

At the moment I'm trying to take variables with an attribute 
(rep) and then make a duplicate of them inside the struct. It 
seems to work. If I had duplicate names, it fails. However, the 
new fields don't appear to be showing up on a second enumeration:


     enum rep;
     struct multiplayerObject2
     	{
     	@rep ushort type;
     	@("rep2") ushort type2;
     	float x, y;
     	
     	static foreach(t; typeof(this).tupleof)
     		{
     		// no if rep/rep2 here, i'm just testing:
     		pragma(msg, t.stringof); // does not see any new fields!
     		mixin("bool " ~ t.stringof ~ "25;"); // copy the fieldname 
with a suffix
     		}

     	pragma(msg, "-----separator-----");

     	static foreach(t; typeof (this).tupleof) // again
     		{
     		pragma(msg, t.stringof); // does not see any new fields!
     		}
     	}


output
```
type
type2
x
y
-----separator-----
type
type2
x
y
```

However, if I do try to force the names to duplicate (say 
"type2") I get an error involving some sort of __anonymous 
subobject.
```
source/app.d-mixin-123(123,6): Error: variable 
`app.multiplayerObject2.__anonymous.type2` conflicts with 
variable `app.multiplayerObject2.type2` at source/app.d(116,19)
```

I also never realized you could put a static/static foreach 
inside the body of a struct (and not a function) so I'm still 
having trouble wrapping my head around that. Is it processing 
top-down?

Jonathan M Davis: Yeah, it does what I listed if you add the UDA 
to it.