If D becomes a failure, what's the key reason, do you think?

[Brad Roberts]

David Medlock wrote:
> Walter Bright wrote:
>> Tesuji wrote:
>>
>>> In article <e8l426$26o3$1 at digitaldaemon.com>, Don Clugston says...
>>>
>>>> It's all in the libraries. D is a fantastic language to write 
>>>> libraries for. That's where you get the benefit from all the 
>>>> incremental improvements. If const-by-default enables the creation 
>>>> of much better libraries, then it's worth the pain. If it doesn't, 
>>>> don't do it.
>>>> Ruby had this huge surge in popularity not because of the language, 
>>>> but because of the library Ruby On Rails. Developing good libraries 
>>>> requires a stable language, and we don't have that right now. The 
>>>> protection/module system seems to be completely broken.
>>>
>>>
>>> Agreed, in addition I also believe that a const-by-default C++ like 
>>> reference
>>> type is needed before any container library (like DTL) can be 
>>> effectively
>>> written. Currently D is lacking in this area where C++ is strongest. 
>>> relying
>>> solely on built-in array / hash is hardly the solution.
>>
>>
>> I don't understand why either of these would *prevent* effective 
>> libraries from being built. Neither enables new programming techniques 
>> or paradigms, they are just aids to documentation and debugging.
> 
> I feel the same.  Libraries either
> a) Are passed allocated objects, in which they are allowed to manipulate 
> them.  No need for const there(that I can see).
> 
> b) Allocate and return objects/data.  Definitely no need for const there.
> 
> Java has tons of libraries, as does Ruby, and Perl, and C, and tons of 
> other libraries without const.  No offenses intended, this is bordering 
> on an obsession.
> 
> With garbage collection, I just don't see the HUGE benefits of const....
> -DavidM

This seems to only include 'core' type libraries.  Application level 
libraries often take in business level objects that often should be for 
'looking but not touching'.  Even intrinsic types, like strings, fall 
squarely into that bucket.

I don't understand the argument against having the concept of const-ness 
  in a language.  That other languages don't have the concept doesn't 
make the concept irrelevant.  I can see there being an interesting 
debate over it being the default state of objects.  I'm personally 
_very_ interested in trying default const for a few months to see how it 
feels.

If it's not obvious, I'm squarely in the camp of language/contractually 
enforced const is good and I want it.

Later,
Brad