Why doesn't `opAssign` work for my templated struct?

[monkyyy]

On Friday, 8 November 2024 at 21:55:53 UTC, Liam McGillivray 
wrote:
> if(isNumeric!T)
> ```
> Error: cannot implicitly convert expression `40.0F` of type 
> `float` to `Milligrams`
> ```

I dont believe phoboes type detection templates are well 
designed; given some sort of type pattern matching issue you 
should write your own with the pattern

```
void dummyNumbericFunction(T)(T t){
   auto foo=t+t;
   ...
}
enum isNumbertic(T)=__traits(compiles,dummyNumbericFunction!T);
```