on Fri Jan 25 2013, Andrey Semashev <andrey.semashev-AT-gmail.com> wrote:
On Friday 25 January 2013 11:30:26 Beman Dawes wrote:
On Thu, Jan 24, 2013 at 8:56 PM, Dave Abrahams <dave@boostpro.com> wrote:
I'm finding that boost::filesystem::path seems to be a strange mix of different beasts, unlike any entity we have in the STL. For example, when you construct it from a pair of iterators, they're expected to be iterators over characters, but when you iterate over the path itself, you are iterating over strings of some kind (**). Even though, once constructed, this thing acts sort of like a container, it supports none of the usual container mutators (e.g. push_back, pop_back, erase) or even queries (e.g. size()), making it incompatible with generic algorithms and adaptors.
It isn't really a container, but it is convenient to supply iterators over the elements of the contained path. Should more container-like mutators be supplied? I'm neutral - they would occasionally be useful, but add more signatures to an already fat interface.
IMHO, path should not pretend to be a container. Things like push_back, insert, erase don't make sense with respect to it.
As soon as you can iterate it and append path elements (and you can now), push_back, insert, and erase make wonderful sense. I understand exactly what those operations should mean, and I have use cases to boot!
It could provide begin/end iterators over underlying characters but just to implement other algorithms. Iterating over path elements (i.e. what is currently achieved with begin/end) should probably be an external tool, like an iterator adaptor or a view on top of the path object. In the end it should become just a thin wrapper over a string, with a few path-related functions.
Why? IME path manipulation almost universally occurs on directory boundaries, so xposing a character-based interface as the primary one for path seems counter-productive. IMO there should be a way to get to the underlying characters if you want them, but the primary interface should be a container of pahth elements. -- Dave Abrahams BoostPro Computing Software Development Training http://www.boostpro.com Clang/LLVM/EDG Compilers C++ Boost