More exception classes into Phobos?

[Георгий via Digitalmars-d]

On Thursday, 23 March 2017 at 09:31:23 UTC, Георгий wrote:
>
> NotImplementedException : Exception
> UserInputException : Exception
> IOException : Exception

I am not sure already, NotImplementedException should be in 
Phobos. Something like this may be a part of vibe.d.

But I still vote for two others. Especially for IOException.
It's too common! It needed everywhere. Why every library, that 
works with streams, need to implement its own exception class for 
this?