"in" everywhere

[Steven Schveighoffer]

On Thu, 07 Oct 2010 16:23:47 -0400, Rainer Deyke <rainerd at eldwood.com>  
wrote:

> On 10/7/2010 13:57, Andrei Alexandrescu wrote:
>> On 10/7/10 14:40 CDT, bearophile wrote:
>>> Another solution is just to accept O(n) as the worst complexity for
>>> the "in" operator. I don't understand what's the problem in this.
>>
>> That means we'd have to define another operation, i.e. "quickIn" that
>> has O(log n) bound.
>
> Why?
>
> I can't say I've ever cared about the big-O complexity of an operation.

Then you don't understand how important it is.  Here is an example of how  
caring about the big O complexity cut the runtime of dmd to about 1/3:

http://d.puremagic.com/issues/show_bug.cgi?id=4721

big O complexity is very important when you are writing libraries.  Not so  
much when you are writing applications -- if you can live with it in your  
application, then fine.  But Phobos should not have these problems for  
people who *do* care.

What I'd suggest is to write your own function that uses in when possible  
and find when not possible.  Then use that in your code.

-Steve