Weird writeln behavior with associative arrays

[Jens Mueller]

Hi,

this program
import std.stdio;

void main() {
        double[string] foo;
        foo["test"] = 10;
        foo["atadfest"] = 10;
        // fails if foo.length > 1
        writeln(foo);
}

fails with:
phobos/std/format.d(1088): Enforcement failed

Am I not allowed to to this? If I have only one element, then it works
as expected. If I change double to int, then I get "test:10 a:10". So
somehow only the first character is displayed. Maybe a phobos bug? Any
ideas?

I'm using Linux and latest dmd.
$ dmd | head -n1
Digital Mars D Compiler v2.049

Jens