On Mon, 2009-06-22 at 08:53 +0200, Deniz Dogan wrote: > 2009/6/22 Colin Paul Adams <co...@colina.demon.co.uk>: > >>>>>> "Judah" == Judah Jacobson <judah.jacob...@gmail.com> writes: > > > > Judah> On Sun, Jun 21, 2009 at 11:12 PM, Colin Paul > > Judah> Adams<co...@colina.demon.co.uk> wrote: > > >> I've been hoogling like bad to try to determine if a function > > >> like this exists. > > >> > > >> getDirectoryContents returns sub-directories as well as file > > >> names. I want only the latter, so I'm looking for a suitable > > >> filter. > > > > Judah> Use System.Directory.doesDirectoryExist/doesFileExist. > > > > Thanks. > > > > it seems it's time i went to the optician again. > > I'm not surprised that anyone would make the mistake. I think that the > two functions should be named "isDirectory" and "isFile", but it seems > that "isDirectory" was already taken by another function in > System.Directory, which is quite unfortunate. "does" goes against the > intuition one gets from pretty much everything else in Haskell, where > "is" seems to be the convention. In fact, Hoogle only knows about > three functions which start with "does".
One explanation is that isBlah asks "is this thing a blah", but we're not asking that because there is an indirection via the filepath. We're asking "does this filepath refer to a directory" not "is this filename a directory". The latter could be a function: isDirectory :: FileInfo -> Bool along with a hypothetical getFileInfo :: FilePath -> IO FileInfo Duncan _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe