Revised RFC on range design for D2

[Pablo Ripolles]

Bill Baxter Wrote:

> On Sat, Sep 13, 2008 at 12:03 AM, Andrei Alexandrescu
> <SeeWebsiteForEmail at erdani.org> wrote:
> > Bill Baxter wrote:
> >>
> >> On Fri, Sep 12, 2008 at 11:39 PM, Andrei Alexandrescu
> >> <SeeWebsiteForEmail at erdani.org> wrote:
> >>>
> >>> Pablo Ripolles wrote:
> >>>>
> >>>> What about "isDone"?
> >>>
> >>> isDone is great, I just wanted to keep the one-word streak going. Let's
> >>> see
> >>> what everyone else says.
> >>
> >> Hmm.  std.algorithm does have an "isSorted" function.  So I guess I
> >> agree it would be more consistent if you call it isDone or isEmpty.
> >>
> >> Or rename "isSorted" to "sorted".  :-)  But then you have to face the
> >> consequences later when you want to have a predicate that is ambiguous
> >> without the "is".    Probably a lot of noun predicates are in that
> >> category -- i.e. checking  isSomeNoun(x).  Like "isRange(x)" to see if
> >> x is a range.  That would have to just become "range(x)" which is a
> >> bit ambiguous.
> >>
> >> So I agree. Stick the "is" in there.
> >
> > Thing is, people will call isSorted much less often than (isD|d)one. In
> > std.algorithm clearly the one-word paradigm can't scale. But for a handful
> > of heavily-used names I'd be willing to take the Pepsi challenge.
> >
> > Andrei
> >
> > P.S. The more I think of it, the more I like "tip" of the range. Short,
> > poignant, easy to remember. Not pressing the red button just yet.
> 
> Hmm.  One semantic issue I have is that the tip usually refers to the
> infinitessimal point at the end.  Not a thing with substance.  I'm
> having trouble feeling like I'm going to get an item back when I look
> at "x.tip".  Head has huge history being used for the item at the
> front of a list, so I think that's much less likely to cause anyone
> looking at D code to scratch their heads.  It will be obvious what it
> means even in relative isolation.  head/tip will often appear without
> "toe" in forward range algos.  So you need to be able to easily
> recognize what "tip" means without seeing that "toe" to give context.
> Toe on the other hand will probably almost always appear with his
> mate.
> 
> Ooh, another scale thing, but a head is obviously a very different
> scale than a toe.  A foot is closer to the same scale.  Maybe
> head/foot is better than head/toe.  The connection between retreating
> / feet is stronger that retreating / toes, too!
> 
> --bb

After having had some sleep, I kind of support Bill's proposal, that is, head/foot, definitely better than head/toe.  It's like the header and the footer! sounds very reasonable.  Of course I also like fore/aft, but thats because my aeronautical engineering bias.

tip is too ambiguous.

tail refers to all what comes after the head, not to its tip.

Cheers!