Concurrency Confusion

["岩倉 澪" via Digitalmars-d-learn]

On Saturday, 8 August 2015 at 05:14:20 UTC, Meta wrote:
> I'm not completely sure that it's bad in this case, but you 
> really shouldn't be casting away immutable. It's undefined 
> behaviour in D.

Afaict it is the best way to do what I'm trying to do, and since 
the data is mutable and cast to immutable with assumeUnique, 
casting it back to mutable shouldn't be a problem. Technically 
casting away immutable might be undefined behaviour and it might 
be an ugly hack, but I don't see a more idiomatic solution.