is it possible to learn D(2)?

[Don]

Jeff Nowakowski wrote:
> On 12/18/2010 07:55 AM, Caligo wrote:
>> If there is going to be a D3, will it be backwards compatible with D2?
>>
>> And why is work still being done on the D1 compiler?  Shouldn't it be 
>> marked
>> deprecated so people stop using it and move to D2?
> 
> D1 is stable and only bug fixes are being applied to it. For D2, the 
> post you replied to mentioned compiler bugs several times, and also 
> mentioned unimplemented features.
> 
> D2 has *never* been officially released (like D1 was), though its 
> release was supposed to coincide with the release of Andrei's book.

Where did you get that idea? I've never heard it before.
(Genuine question, I'd like to know where that impression came from).

  The date kept on getting pushed further and further back, until 
finally the
> book came out (publishers only have so much patience), and no mention of 
> D being released was made.
> 
> Walter and Andrei haven't been very honest in their presentations on the 
> state of the language. 

I think the initial estimate of how long things would take was wildly 
optimistic. I am certain that there's been no intention to be dishonest, 
at any stage.

 > I know a software project is never "finished", in
> that you can't expect perfection, but D2 is still in the alpha state. 
> It's not reasonable for features documented in the definitive book on 
> the language to not work. 

Agreed. Unfortunately, the publishers couldn't be delayed any further. 
There are a few things in the book which still don't work, and will take 
another couple of releases to be implemented.
(A few months before release, the list of non-implemented features was 
quite long. Most of the things on the list _were_ implemented in time. A 
couple turned out to be unexpectedly difficult).

> Also, the crown jewel of D2 was supposed to be 
> immutability and concurrency, and those are the buggiest parts.

Well, they are the most difficult bits! So if anything were to be 
incomplete, it would be those.