Checking if something is a template specialization?

[Lars T. Kyllingstad]

On Fri, 18 Feb 2011 02:02:51 +0000, Sean Eskapp wrote:

> If I have
> 
> class Bar(T)
> {
> }
> 
> void foo(Y)()
> {
>    ...
> }
> 
> Is there a way to check inside foo() that Y is in some way an
> instantiation of Bar? Is there a way to find WHICH instantiation it is?


void foo(Y)()
{
    static if (is(Y Z == Bar!Z))
    {
        // Here, Z is now an alias to whichever type Bar is
        // instantiated with.
    }
    else
    {
        // Z is invalid here.
    }
}