lambdas with types

[jmh530 via Digitalmars-d-learn]

Doing something like below fails because I don't seem to be able 
to make a templated lambda that just takes types. Is the only way 
to do something similar to create a separate function to handle 
the condition, or is there some other way to do something with 
similar flexibility?

import std.stdio: writeln;
import std.meta: allSatisfy;
void foo(Args...)(Args args)
    if (allSatisfy!(x => is(x == double), Args))
{
    writeln("works");
}

void main() {
    foo(1.0, 2.0);
}