Re: [Boost-users] bind with boost::filesystem::directory_iterator

From: Daniel Krügler (dsp_at_[hidden])
Date: 2008-04-14 04:07:04

Brad wrote:
> Hi guys and gals,
> 
> I'm new to boost and this is my first attempt to use bind (big step LOL).
> 
> I'm trying to do this:
> 
>     bfs::path p( "." );
>     bfs::directory_iterator dir_iter( p );
>     for_each( dir_iter.begin(), dir_iter.end(), boost::bind( 
> &purgeOlder, _1 )  )
> 
> but I get:
> 
> purgefiles.cpp:53: error: 'class boost::filesystem::directory_iterator' 
> has no member named 'begin'
> purgefiles.cpp:53: error: 'class boost::filesystem::directory_iterator' 
> has no member named 'end'
> 
> It would appear directory_iterator does not have these members which are 
> common on the other containers, am I missing something? Is there a way 
> to do this using bind?

This has nothing to do with bind. As you say, begin()/end() would
be available for a *container*, but - as the name says - 
directory_iterator is just an iterator, not a container. If you follow
the documentation, you will find out, that the default constructed
directory_iterator corresponds to "end" and that there exists one
further c'tor that accepts a path - this is the one you should use
in replacement for begin.
For a better understanding of the idea behind that you should compare
directory_iterator with existing std iterator adaptors, like the insert 
iterators or the stream iterators.

HTH & Greetings from Bremen,

Daniel Krügler