is this a bug? (aa initializer)

[Lutger]

With dmd 2.017:

import std.stdio;

void main()
{
    string[string] foobar =  [ "foo" : "bar" ];
       foreach (key, value; foobar)
           writefln(key, value); // prints foobar
    assert(foobar["foo"] == "bar"); // arraybounds error
}

Could somebody verify this as a bug or not? I'm not sure because I just
started with D2 a bit.