Does `is` expression with template alias need fixing.

[jmh530]

On Wednesday, 22 March 2023 at 11:00:40 UTC, zjh wrote:
> On Wednesday, 22 March 2023 at 10:43:15 UTC, Elfstone wrote:
>> ```C++
>> template <typename T>
>> using Vector3 = Matrix<T, 3, 1>;
>> ```
>>
>> I declare an alias and I use it everywhere. It acts as a 
>> natural constraint. I never needed `isVector3` with my old C++ 
>> code. I expected D could do the same, and was really 
>> frustrated when I found out it couldn't. Even more frustrated 
>> when I read Steven's reply, that the bug with `is` has been 
>> there for 16 years.
>>
>
> When you have questions, please file a bugzilla.
> D is only for `specific problems`, please describe the problem 
> carefully.

What the OP is referring to is an old D bug [1]. In this thread, 
he's not really asking questions so much as highlighting that it 
is still an issue.

[1] https://issues.dlang.org/show_bug.cgi?id=1807