Speed up compilation of CTFE-heavy programs with this One Weird Trick!

[Andrei Alexandrescu via Digitalmars-d]

On 11/02/2016 11:43 PM, Vladimir Panteleev wrote:
> For each function that is only called during compilation (e.g. for code
> generation), at the top add:
>
>     if (!__ctfe)
>         return;
>
> That's it. For one project, this brought compilation time (with
> optimizations) from over an hour down to seconds!
>
> As it turns out, DMD will codegen all functions, even templated ones
> when they're instantiated, whether they're called by something or not.
> With metaprogramming-heavy code, it's easy to run into some optimizer
> performance corner cases, however this may make an impact regardless.
>

That's interesting. cc Dmitry, perhaps adding that to ctRegex would be 
helpful. -- Andrei