Beman Dawes <[EMAIL PROTECTED]> writes: > At 03:55 PM 8/21/2003, David Abrahams wrote: > > >Beman Dawes <[EMAIL PROTECTED]> writes: > > > >> At 08:31 PM 8/19/2003, David Abrahams wrote: > >> > > >> >It surprised me a bit that leaf returns a string instead of a path. > >> > >> The rule isn't entirely obvious. If a decomposition function can > >> possibly return more that one element, it is returned as type path. If > >> at most a single element is returned, the return type is std::string. > > > >It may not surprise you, but the easy translation between paths and > >strings really rubs me the wrong way. Practically the only reason I'm > >using the path class at all is to increase the level of abstraction > >and self-documentation of the code I'm writing -- I think it's foolish > >to pass around something called std::string when it really represents > >a file path. A single component of a path is still a path, and it > >shouldn't devolve into a string. > > > >I'm rewriting some Java code in C++ which has a "Directory" > >abstraction, that lets you open files in that directory. I want those > >functions take path parameters. I want to assert that they're leaf > >paths. Having to write: > > > > assert(path(p.leaf()) == p) > > > >or > > > > assert(p.leaf() == p.string()) > > > >instead of: > > > > assert(p == p.leaf()) > > > >really feels odd to me. > > What about: > > assert( p.branch_path().empty() ); > > Isn't that closer to what you are trying to express?
I guess so. I didn't see branch_path(). > >> >Shouldn't > >> > > >> > "foo/bar"/p.leaf() > >> > > >> >work? > >> > >> Yes, via the automatic conversion. I just added a test case to > >> path_test to verify that. Yes, it does work. I expect there would > >> have been scads of bug reports if it didn't work. > > > >Whoa. What code and compiler did you test that with? > > Ah! I corrected your code first so that "foo/bar" was a path. There is > no operator/ for string arguments, of course. Of course; that was the point of what I was saying. you can write cstring/path, but not cstring/std::string; I think it's reasonable to combine the leaf of a path with path strings if that's something you can normally do with a full path. -- Dave Abrahams Boost Consulting www.boost-consulting.com _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost
