Should the comma operator be removed in D2?

[Justin Johansson]

Ellery Newcomer wrote:
> Ellery Newcomer wrote:
>> Bill Baxter wrote:
>>> Yes, Yigal said basically that.  The question I have is what practical
>>> difference does that make to the language?
>>> Seems no different from defining the empty tuple to be void, then
>>> renaming void to unit.
>>>
>>>
>>> --bb
>> If you have unit distinct from void, you could use it for what Andrei
>> mentioned a while back. Something to do with determining a function will
>> never return because it always throws, etc.
> 
> then again, maybe not.

 From my memory of Scala, the top and bottom types are called
Unit and Nothing respectively.  Unit is analogous to C,C++,D,Java void 
and Nothing is the type of that returned by a function that never 
returns (in other words nothing).  I think the latter (the Nothing type) 
is what Andrei was talking about before.

FYI, a lot of articles about types systems are rather arduous to read 
but I found this one written in more lay-speak by James Iry who is a 
Scala advocate.

Getting to the Bottom of Nothing At All.

http://james-iry.blogspot.com/2009/08/getting-to-bottom-of-nothing-at-all.html

Enjoy the read; all about nothing, bits about tuples. No warranty for 
academic accuracy though.

-- Justin Johansson