Re: [boost] [mpl]iter_fold_if Forward Backward rationale?

on Sun Apr 05 2009, Larry Evans <cppljevans-AT-suddenlink.net> wrote:

Just as the ForwardPredicate is "augmented" with protection against dereferencing the end<numbers>::type in this code:

https://svn.boost.org/trac/boost/browser/trunk/boost/mpl/iter_fold_if.hpp#L4...

shouldn't the BackwardPredicate also be augmented with the same protection here:

https://svn.boost.org/trac/boost/browser/trunk/boost/mpl/iter_fold_if.hpp#L7...

Well, it doesn't need to be; if it did, tests and uses wouldn't compile ;-) Just think about how you'd implement it and it should become obvious why. -- Dave Abrahams BoostPro Computing http://www.boostpro.com