The following code fails to compile for me:
#include <memory> #include <boost/iterator/transform_iterator.hpp>
std::unique_ptr<int> foo(int i) { return std::unique_ptr<int>(new int(i)); }
int main() { int a[5] = {1, 2, 3, 4, 5}; auto it = boost::make_transform_iterator(a, foo); }
The error message I get with GCC 4.8 is pasted below.
I think this should work because returning a move-only type from a function by value is a perfectly valid thing to do. Do you agree? Should I file a bug?
Seems reasonable, but upon an initial inspection, this looks like a hiccup in boost::is_convertible...I'm not saying that once that gets sorted out, there won't be something wrong in boost::transform_iterator, but is_convertible should probably be addressed first.
In any case, this looks like this same problem that John Bytheway identified in the thread titled "[boost] [type_traits][parameter] Inconsistent boost::is_convertible between gcc and clang".
Ah, I see, this works with the latest trunk (which includes the patch posted in that thread). Thanks for the heads up! Regards, Nate