Justin Johansson wrote: > There was mention** on the general discussion group that the D foreach_reverse > language construct could be replaced (emulated?) with a (D) meta-program. > > ** "Even a novice programmer can write a meta-program to replace > foreach_reverse without any runtime performance hit." > > > http://www.digitalmars.com/webnews/newsgroups.php?art_group=digitalmars.D&article_id=97362 > > As I'm less than a novice with the D meta-programming facilities (at this > stage of my journey into D), > if someone would kindly show me the D meta-program solution to do this, > I'd really appreciate the enlightenment. > > Thanks again.
Short answer: you can't. Long answer: you can, provided you aren't trying to reverse an opApply, which is patently impossible. As for the "meta-program", I would suspect whoever said that was talking about writing a templated type or function to handle it. You would need to use template specialisation or static ifs to switch on what type you've been given to reverse. http://digitalmars.com/d/1.0/template.html http://digitalmars.com/d/1.0/version.html#staticif
