Hello folks. I'm trying to use the iter_fold and reverse_iter_fold
algorithms in MPL, since I want to operate on sub-ranges of an input
sequence. Now if I do just the trivial case of dereferencing the
current element, then all is well:
struct works
{
typedef typename reverse_iter_fold<
T,
vector_c<long>,
push_front<_1,
deref< _2 >
> >::type type;
};
I can successfully instantiate this with, for example,
vector_c. But when I do iterator arithmetic (e.g. prior,
next or begin) I run into trouble:
struct fails
{
typedef typename reverse_iter_fold<
T,
vector_c<long>,
push_front<_1,
deref< next<_2> >
> >::type type;
};
-- error messages about arg 3 - I suspect that prior is being applied
to the placeholder arg type itself, not to the iterator. I'm wondering
if I should be using lambda/apply, but I've tried that without
success. What's a would-be template metaprogrammer to do?
Regards
Rob
