usage of ref foreach with variadic functions fails with "cannot be ref"

[error via Digitalmars-d-learn]

On Saturday, 11 February 2017 at 14:43:18 UTC, rikki cattermole 
wrote:
> Try:
>
> foreach(i, v; vars) {
> 	vars[i] = ...;
> }

Perfect! Thanks so much - I wish that hint was in the 
documentation for variadic functions, although I guess it 
suggests an inefficiency in the compiler - since there would be 
an additional copy of vars[i] created in v.