...an error whenever it sees a template alias in `is` expression, because currently the result...

...use a template alias (which s/he may not know is an alias) in an...

...template and the thing it gets:

```d
alias Foo(T) = int;

// the following are equivalent...

...d
alias VariableAllocator = ThreadLocal!(FreeList!(Mallocator, Variable.sizeof, unbounded));
```

should be this instead:

```d
alias...

...variableAllocator = allocatorObject(FreeList!(Mallocator, Variable.sizeof, unbounded)());
alias VariableAllocator = ThreadLocal!(FreeList!(Mallocator, Variable.sizeof, unbounded...

...is(S == int))
        alias Vec3_alt = Matrix!(S, 3, 1);
    else
        alias Vec3_alt = real...

...25): Error: struct `test.PgHdr` conflicts with alias `test.PgHdr` at /pcache.h(18)
```

```c...

The compiler should at least report it as an error: `is` cannot handle template alias.

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

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

void...

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

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

void...