dcollections 1.0 and 2.0a beta released

[Robert Jacques]

On Thu, 20 May 2010 06:34:42 -0400, Steven Schveighoffer  
<schveiguy at yahoo.com> wrote:
> Robert Jacques Wrote:
>
>> On Wed, 19 May 2010 21:42:35 -0400, Steven Schveighoffer
>> >
>> > Does that make sense?
>> >
>> > -Steve
>>
>> Yes and No. I understand where your coming from, but I think it's a bad
>> idea. First, I think it needlessly expands the radius of comprehension
>> needed to understand and use the library. (See Tangled up in tools
>> http://www.pragprog.com/magazines/2010-04/tangled-up-in-tools) Second, I
>> think designing a library to be flexible enough to meet some future,
>> anticipated need (e.g. dlls) is a good idea, but actually implementing
>> vaporous future needs is fraught with peril; it's too easy to guess  
>> wrong.
>> Third, interface base design is viral; If library X uses interfaces  
>> then I
>> have to use interfaces to interface with it. And if another library Y  
>> uses
>> classes, then I'm going have to write a (needless) wrapper around one of
>> them.
>
> I understand these points, but I'm already using interfaces to copy data  
> between containers.  I don't have to, I could have used generic code,  
> but this way, only one function is instantiated to copy data from all  
> the other containers.  The problem with using generic code is that the  
> compiler will needlessly duplicate functions that are identical.

This sounds like a failure of design. Why aren't you using ranges to do  
this?

> Using interfaces is not as viral as you think.  My interfaces can be  
> used in generic code, as long as the generic code uses functions in the  
> interfaces.  If a library returns an interface, the author is saying "I  
> don't want you using any functions outside this interface," so why is  
> that a bad thing?

Well, needlessly duplicated functions for one. :) More importantly, the  
example I gave was about third party libraries which I have no control  
over. So this solution explicitly doesn't work. And even if everyone used  
templates everywhere in order to be compatible with both interfaces and  
classes, isn't that a viral effect of having both?

> Forcing people to *not* use interfaces has its drawbacks too.   
> Dcollections gives the most flexible design I could muster, while still  
> being useful.
>
> I'm not saying I'm against removing the interfaces until some later  
> date, but I don't see any convincing arguments yet, especially since  
> I've already seen benefits from having them.
>
> -Steve