Jarrett Billingsley wrote:
On Fri, Oct 9, 2009 at 4:57 PM, Sean Kelly <s...@invisibleduck.org> wrote:
== Quote from Andrei Alexandrescu (seewebsiteforem...@erdani.org)'s article
Thanks!
I plan to add more text at the end of the chapter that discusses the
opportunities of CTFE. Walter revealed to me that CTFE, particularly now
after it's been improved by leaps and bounds by Don and by Walter
himself, could obviate a lot of the traditional metaprogramming
techniques developed for C++.
One question that bugs me is, where do you draw the line? Say there's a
metaprogramming problem at hand. How to decide on solving it with CTFE
vs. solving it with templates? It would be great to have a simple
guideline that puts in contrast the pluses and minuses of the two
approaches.
CTFE is great for working with values while template metaprogramming is
great for working with types. String mixins make CTFE good at working
with types as well, but I wouldn't consider them a novice-level feature.
Throw templates in there. Boom! Goodbye, CTFE.
(.stringof and templates do not get along.)
That's just a bug. The more fundamental problem is that you can't
instantiate a template from inside CTFE. IE, you can cross from the
"compile-time world" to the "runtime world" only once -- you can never
get back.
