C Macro deeper meaning?

[Andrew Edwards via Digitalmars-d-learn]

If I understand correctly, this piece of code:
    enum NOTUSED(v) do { (void)(1 ? (void)0 : ( (void)(v) ) ); } 
while(0)

can be converted to the following in D:

    void notUsed(T)(T v) { return cast(void)0; };

since it always returns cast(void)0 regardless of the input.

But it cannot be that simple, so what am I missing?

Thanks,
Andrew Edwards