There's a problem with this approach: I'll have to specialize `Vector Matrix.opBinary...

...error: "don't you ever put template alias in `is(...)`". The current behaviour is confusing...

https://issues.dlang.org/show_bug.cgi?id=21288

--- Comment #6 from Dlang Bot <dlang...

...as a `struct` with `alias this` instead of as an `alias`:

```d
struct Matrix(S...

...from some concrete type to the template alias.

[1] https://issues.dlang.org/show_bug...

I recently faced a similar problem.

```d
import std;
static assert(isInstanceOf!(Array, Array!char...

...S, size_t M, size_t N)
{
}

alias Vec3(S) = Matrix!(S, 3, 1);

void...

...on an existing alias, which defeats the supposed meaning and purpose of `alias`.

I hope...

...N, V)))
        {
            alias enum isVec3 = N == 3;
            alias enum isVec2 = N == 2;

            alias enum isVaildVec...

...can get worse.

```D
alias Vec2(S) = Vector!(S, 2);
alias Vec3(S) = Vector!(S...