howto count lines - fast

[Jordan Wilson via Digitalmars-d-learn]

On Tuesday, 30 May 2017 at 20:02:38 UTC, Nitram wrote:
> After reading 
> https://dlang.org/blog/2017/05/24/faster-command-line-tools-in-d/ , i was wondering how fast one can do a simple "wc -l" in D.
>
> So i made a couple short implementations and found myself 
> confronted with slow results compared to "/usr/bin/wc -l".
>
> How would a implementation look like in D, which is fast?

Not sure if this is the fastest, but anyway

void main(){
     import std.file : read;
     import std.conv : to;
     import std.algorithm : count;

     auto data = cast(ubyte[])read("somefile.txt");
     auto lc = data.count('\n'.to!ubyte);
}

Jordan