On Thu, Jul 12, 2012 at 1:39 PM, Nathan Ridge <zeratul976@hotmail.com> wrote:
Support for the C++11 range-based for statement and BOOST_FOREACH for directory_iterator and recursive_directory_iterator has been added to trunk. This clears feature requests 5896 and 6521.
The range-based for has been tested against gcc 4.6, which works, and against VC++2012 RC, which ICEs the compiler. The ICE has been reported to Microsoft.
If anyone gives either C++11 range-based for or BOOST_FOREACH a try, I'd appreciate hearing about any problems. Both of these are new to me, and I'm nervous about getting the enabler free functions right.
Here is what usage looks like:
for (directory_entry& x : directory_iterator(".")) { std::cout << " " << x.path() << "\n"; }
BOOST_FOREACH(directory_entry& x, directory_iterator(".")) { std::cout << " " << x.path() << "\n"; }
I'm a little surprised to see a function that returns a range named "directory_iterator".
Other Boost libraries, such as Boost.Iterator and Boost.Range, distinguish between the concepts of an iterator, which denotes a single position in a range, and a range, which is defined by iterators at is beginning and its end.
directory_iterator is like std::istream_iterator in that a directory_iterator object identifies the end of a range simply by being equal to directory_iterator(). Thus these iterators are a little odd in that they self-identify both the beginning and the end of the range. So there is no real distinction between an my_iterator and begin(my_iterator). The only reason the function is there is to meet the range-based for statement requirements. Ditto for BOOST_FOREACH range helper functions.
Have you considered naming the function "directory_range" to be consistent with other Boost libraries?
"directory_iterator" is the constructor for class directory_iterator. I'm happy with that as a name since it identifies the primary use of the class. --Beman