Sub-classing exceptions

[Shriramana Sharma via Digitalmars-d]

Jacob Carlborg wrote:

> If you declare the subclass as usual you can have a template mixin that
> adds the constructor.
> 
> class SubException : Exception
> {
> mixin ExceptionConstructors;
> }

https://github.com/D-Programming-Language/druntime/pull/1413

-- 
Shriramana Sharma, Penguin #395953