Re: [boost] AlRangeExandrescu?

Subject: Re: [boost] AlRangeExandrescu?
From: Thorsten Ottosen (thorsten.ottosen_at_[hidden])
Date: 2009-07-25 14:13:39

Andrei Alexandrescu skrev:
> Thorsten Ottosen wrote:
>> Andrei Alexandrescu skrev:
>>
>>>>> Surprisingly, until() also works on input ranges! It works because 
>>>>> it finds the element lazily - it returns a range that tests for 
>>>>> termination condition in its .empty() test. So until() returns a 
>>>>> range that iterates the original passed-in range until the sought 
>>>>> element is found, at which time until() reports termination.
>>>>
>>
>> Is until lazy for all types of ranges? Being lazy is often good, but
>> it's so nice to compose a lazy range with other types of ranges.

A "not" slipped here.

> Yes, until is lazy. I think it couldn't be implemented any other way for 
> input ranges.

Ok, but the problem with lazy ranges is that when you compose it with
range adaptors, then it greatly limits the adaptors that you can 
subsequently apply.

-Thorsten