GSoC-2011 project:: Containers

[Jonathan M Davis]

On 2011-03-30 01:18, Daniel Gibson wrote:
> Am 30.03.2011 01:55, schrieb Jonathan M Davis:
> > On 2011-03-29 14:50, dsimcha wrote:
> >> == Quote from Jonathan M Davis (jmdavisProg at gmx.com)'s article
> >> 
> >>> The fancier stuff would be nice, but we don't even have a doubly-linked
> >>> list yet. We should get the simpler stuff sorted out before we get
> >>> particularly fancy, not to mention that it's usually the simple stuff
> >>> that gets heavily used.
> >> 
> >> For the most part I agree, but a doubly linked list might be **too**
> >> simple. Linked lists are so trivial to implement that I'd tend to roll
> >> my own that does exactly what I need with regard additional behavior on
> >> insertion, etc. rather than wrapping a library solution to get these
> >> features.
> > 
> > A doubly-linked list is on the list of containers that every standard
> > library should have or it's likely to be considered lacking. I can
> > understand rolling your own for specific uses, but _I_ sure don't want
> > to be doing that if I don't have to. If I want a doubly-linked list, I
> > want to be able to just create a standard one and use it. C++, C#, and
> > Java all have doubly-linked lists in their standard libraries.
> > 
> > If no one else ever implements a doubly-linked list for Phobos, I'll
> > probably do it eventually simply because it's one of the containers that
> > is on the short list of containers that pretty much every standard
> > library has.
> > 
> > - Jonathan M Davis
> 
> It may be feasible to enhance the single-linked list to support both
> single- and double linking, via an additional template-parameter "bool
> doubly" or something like that and some static-ifs in the implementation.
> I once created a simple single/double-linked queue for D1 like that.

To what end though? I don't think that that would save you much. While some of 
the implementation would be the same, so much of it would be different, that 
you'd practically have two complete types defined in one template. At that 
point, you might as well create a separate class/struct. It's just simpler to 
have them separate, and I don't see any real gain in combining them. Having 
both is great, since there are times that you want one and times when you want 
the other, but having both SList and DList (or whatever it would be called) as 
separate types makes sense.

- Jonathan M Davis