We can't.
On Feb 25, 2014 10:46 PM, "johnjbarton" <notifications@github.com> wrote:

> In src/runtime/ModuleStore.js:
>
> > @@ -86,6 +86,15 @@
> >          enumerable: true
> >        });
> >      });
> > +    // es-discuss:
> > +    // On Feb 21, 2014, at 12:08 PM, David Herman wrote:
> > +    // I think it should be Module.isModule.
>
> How can we implement Module.isModule(m) w/o a module keyed map?
>
> —
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> .
>