[Issue 8487] Semantic analysis of templates is insanely slow

[d-bugmail at puremagic.com]

http://d.puremagic.com/issues/show_bug.cgi?id=8487



--- Comment #5 from timon.gehr at gmx.ch 2012-07-31 21:42:23 PDT ---
(In reply to comment #3)
> > Well, the performance can probably be improved, but I'd advise rewriting that
> snippet to use CTFE instead.
> 
> I'm trying to figure out how to do that, and I'll probably manage it, but that
> means using an array instead of TypeTuple, and arrays don't have the benefit of
> forcing CTFE, making it much harder (and the need to have the literals treated
> as literals at the right time and not before also complicates things). It's
> quite clean with TypeTuples (aside from the fact that I'm forced to split it
> across multiple type tuples so that the template instantiations don't choke at
> 100, thinking that they're recursing infinitely), and I'd much prefer to use
> them, but with this poor performance, it's not really reasonable.
> 

See the attachment I created for a possible solution.

> > Templates aren't meant for computation.
> 
> I don't buy that. D's templates are specifically designed in a way to make that
> sort of thing possible, and in this particular case, using templates is
> definitely easier than CTFE.

I disagree.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------