It is the year 2020: why should I use / learn D?

Eugene Wissner belka at caraus.de
Wed Nov 14 18:08:31 UTC 2018


On Wednesday, 14 November 2018 at 17:47:10 UTC, Basile B. wrote:
> On Wednesday, 14 November 2018 at 16:09:32 UTC, Eugene Wissner 
> wrote:
>> No, it wasn't the reason. Some algorithms cannot be 
>> implemented with ranges as efficient as with iterators.
>>
>> "In other words, by converting the is_word_boundary from 
>> iterators to D-style ranges, the algorithm goes from O(1) to 
>> O(N). From this we draw the following conclusion: D’s choice 
>> of algorithmic basis operations is inherently less efficient 
>> than C++’s."
>>
>> C++ iterators are more flexible.
>
> You meant D ?

C++. An iterator points to some element in a range, and you can 
mix it as you need. In D you always have two iterators: beginning 
and the end of the range. The feature I miss most, is a 
bidirectional iterator. In C++ you can go back and forth with 
this iterator. In D if you do popBack there is no way back (or 
front :)); with popFront you can't reach the element after back, 
even if there such elements, you have to take an another range 
from the container.

D ranges are more compact, because you need the begining and the 
end in the most cases, so such functions just take one range 
instead of two iterators. But there are still a lot of cases 
where D ranges don't work.

Steven Schveighoffer mentioned an interesting solution but it 
adds complexity: Implement Range, ConstRange, Cursor, 
ConstCursor?, algorithms that accept ranges or cursors and so 
forth...

>> I think of things like rotate and bringToFront ...




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