D's greatest mistakes

[Andrei Alexandrescu]

On 11/29/10 1:38 PM, Andrei Alexandrescu wrote:
> On 11/29/10 1:35 PM, Steven Schveighoffer wrote:
>> On Mon, 29 Nov 2010 11:52:31 -0500, dsimcha <dsimcha at yahoo.com> wrote:
>>
>>> == Quote from Andrei Alexandrescu (SeeWebsiteForEmail at erdani.org)'s
>>> article
>>>
>>>> Ultimately I believe we need to make Rebindable palatable. That would
>>>> have the nice side effect of enabling other proxy types.
>>>> Andrei
>>>
>>> I've asked before and I'll ask again, what's still wrong with
>>> Rebindable? A bunch
>>> of alias this issues got fixed in 2.050, and I fixed a bunch of misc.
>>> convenience
>>> issues a few releases ago. I fail to see the problem with it anymore.
>>
>> Every few months or so, someone finds a problem with it. It seems that
>> it's good enough in theory, but miserably fails in practice when someone
>> tries to use it. I admit I haven't looked at it in a while, but there
>> are implicit casting problems that cannot be solved without compiler
>> help. I just think Rebindable will get more and more convoluted until
>> someone finally admits that this is better served as a builtin feature.
>
> I don't grok this. If people find different issues with it that are
> fixed, then there is progress, right? (Clearly "escaping" into the
> language makes things better.)
>
>> One of those issues:
>>
>> import std.typecons;
>>
>> class C {}
>>
>> void foo(Rebindable!(const C) c)
>> {
>> }
>
> Let me fix that:
>
> void foo(const C c)
> {
> auto rc = Rebindable!(const C)(c);
> ...
> }

That also reminds me we need a function:

void foo(const C c)
{
     auto rc = rebindable(c);
     ...
}



Andrei