const and immutable objects

[Andrei Alexandrescu]

Jeremie Pelletier wrote:
> Graham St Jack Wrote:
> 
>> On Sun, 30 Aug 2009 21:28:18 -0400, Jeremie Pelletier wrote:
>> 
>> 
>>> I agree that D lacks a mechanism to separate the object from it's
>>>  reference. Maybe syntax like the following could be used to
>>> apply the storage class to the object value, and not the
>>> reference value:
>>> 
>>> class Foo; void bar(in Foo& foo) {}
>>> 
>>> It's quite ugly and C-like, but that's the first thing that came
>>> to mind. The reference value is unique to the current method and
>>> shouldn't share the same storage qualifiers as it's referenced
>>> memory.
>> I think the time for pining over this particular syntax feature of
>> D is over - as nice as it would be to be able to fix the problem in
>> the language, it would be too disruptive right now.
> 
> I think it would be better to fix it in D2  instead of patching a
> language design flaw with a template. It wouldn't be the first time
> D2 has changes that breaks existing code anyways (and the upcoming
> T[new] will definitely break a lot of code, so does shared when it
> works, etc), so it would be less disruptive to do it now than never
> do it.

I agree with the sentiment. The issue is, however, that the change adds 
a fair amount of complexity to the const system for an arguably 
not-often-used need.

Andrei