Simple performance question from a newcomer

[dextorious via Digitalmars-d-learn]

On Sunday, 21 February 2016 at 16:20:30 UTC, bachmeier wrote:
> First, a minor point, the D community is usually pretty careful 
> not to frown on a particular coding style (unlike some 
> communities) so if you are comfortable writing loops and it 
> gives you the fastest code, you should do so.
>
> On the performance issue, you can see this related post about 
> performance with reduce:
> http://forum.dlang.org/post/mailman.4829.1434623275.7663.digitalmars-d@puremagic.com
>
> This was Walter's response:
> http://forum.dlang.org/post/mlvb40$1tdf$1@digitalmars.com
>
> And this shows that LDC flat out does a better job of 
> optimization in this case:
> http://forum.dlang.org/post/mailman.4899.1434779705.7663.digitalmars-d@puremagic.com

While I certainly do not doubt the open mindedness of the D 
community, it was in part Walter Bright's statement during a 
keynote speech of how "loops are bugs" that motivated me to look 
at D for a fresh approach to writing numerical code. For decades, 
explicit loops have been the only way to attain good performance 
for certain kinds of code in virtually all languages (discounting 
a few quirky high level languages like MATLAB) and the notion 
that this need not be the case is quite attractive to many 
people, myself included.

While the point Walter makes, that there is no mathematical 
reason ranges should be slower than loops and that loops are 
generally easier to get wrong is certainly true, D is the first 
general purpose language I've ever seen that makes this sentiment 
come close to reality.