A few improvements to SortedRange

[Andrei Alexandrescu]

On 1/27/11 12:43 PM, bearophile wrote:
> Andrei:
>
>> I just committed a few improvements to phobos' SortedRange, notably
>> adding various search policies and improving the existing routines.
>> These changes will be rolled out in the next dmd release. Until then,
>> feel free to suggest any improvements.
>
> That SearchPolicy will be enough for maniacs too (it just lacks optional galloping sound effects), very good Andrei :-)
>
> Bye,
> bearophile

In fact I implemented it because many large-scale algorithms (such as 
n-way merge or intersection) use galloping search as a primitive. One 
nice perk is that having galloping search available allowed me to 
improve equalRange, which is often of use in casual applications.

Right now equalRange is arguably better than all other implementations 
I've seen because once it found one element that's inside the equal 
range, it performs galloping searches to the left and to the right to 
find the limits of that range. Other implementations I've seen use 
straight binary search for finding those limits, which I think is 
inferior because most often the limits of the equal range are close to 
the found point.


Andrei