How is std.traits.isInstanceOf supposed to work?

[Tommi]

On Sunday, 10 November 2013 at 23:43:21 UTC, TheFlyingFiddle 
wrote:
> The template isInstanceOf checks to see if the second parameter 
> is a template instantiation of the first parameter.

But in this example of mine:
isInstanceOf!(SuperSt, SubSt)
...the second parameter is not a template instantiation of the 
first parameter, yet isInstanceOf evaluates to true.


I think what this all boils down to is that this is a 
compiler-bug:

struct A(T)
{}

struct B
{
     A!int _a;
     alias _a this;
}

void main()
{
     static assert(!is(B == A!int)); // OK
     static assert(is(B == A!T, T)); // BUG (shouldn't compile)
}