On Fri, Mar 04, 2022 at 07:51:44PM +0000, matheus via Digitalmars-d-learn wrote: [...] > for(j=0;j<1_000_000;++j){ > s=""; > s = str.filter!(ch => ch.isDigit).to!string;
This line allocates a new string for every single loop iteration. This is generally not something you want to do in an inner loop. :-) > } [...] > Unless I did something wrong (If anything please tell). By the way on > DMD was worse, it was like 5x slower in your version. [...] I don't pay any attention to DMD when I'm doing anything remotely performance-related. Its optimizer is known to be suboptimal. :-P T -- Study gravitation, it's a field with a lot of potential.