Struct that destroys its original handle on copy-by-value

[Joseph Rushton Wakeling via Digitalmars-d-learn]

On 26/07/15 13:45, Martijn Pot via Digitalmars-d-learn wrote:
> Sounds like unique_ptr (so UniqueRange might be a nice name). Maybe you can get
> some ideas from that.

There is already a Unique in std.typecons.  However, I'm not sure that it's 
doing what I require.

Example:

     Unique!Random rng = new Random(unpredictableSeed);
     rng.take(10).writeln;

... will fail with an error:

     Error: struct std.typecons.Unique!(MersenneTwisterEngine!(uint, 32LU, 
624LU, 397LU, 31LU, 2567483615u, 11LU, 7LU, 2636928640u, 15LU, 4022730752u, 
18LU)).Unique is not copyable because it is annotated with @disable

My aim by contrast is to _allow_ that kind of use, but render the original 
handle empty when it's done.