How to foreach over a DList?

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On Tuesday, 1 April 2014 at 12:30:03 UTC, monarch_dodra wrote:
> I fixed this not too long ago. Long story short, the "~=" 
> implementations were made of fail.
>
> Just change those "~=" for "insertBack" and you should be fine.

That aside, why is it necessary to cast 1, 2 and 3 to ubyte when 
adding them to the DList? Is this a problem with DList or with D?