Poor regex performance?

[Stefan Koch]

On Thursday, 4 April 2019 at 10:31:43 UTC, Julian wrote:
> On Thursday, 4 April 2019 at 09:57:26 UTC, rikki cattermole 
> wrote:
>> If you need performance use ldc not dmd (assumed).
>>
>> LLVM has many factors better code optimizes than dmd does.
>
> Thanks! I already had dmd installed from a brief look at D a 
> long
> time ago, so I missed the details at 
> https://dlang.org/download.html
>
> ldc2 -O3 does a lot better, but the result is still 30x slower
> without PCRE.

You need to disable the GC.
by importing core.memory : GC;
and calling GC.Disable();

the next thing is to avoid the .idup and cast to string instead.