From: Daniel Berger <djberg96@...>
Date: 2007-09-29T04:12:22+09:00
Subject: Re: is there to invoke 'previous' in Find? (or refresh the current path?)



On Sep 27, 4:10 pm, "dtow...@gmail.com" <dtow...@gmail.com> wrote:
> I am writing a small script which recursively goes down a dir
> hierarchy, and when it reaches a set of files, it applies a 3rd party
> application which modifies those files, and prepends the name with
> "Mod-".
>
> So for example, if i had a directory with only 1 file: C:\myDir
> \myFile.txt, and I ran the app, I would end up with the following
> files in c:\myDir
>
> myFile.txt
> Mod-myFile.txt
>
> Basically, what i want to do is traverse down the hierarchy, when i
> reach a set of files, call the app on that directory, then delete the
> original, and rename the new file so that the "Mod-" is removed.
> Unfortunately, the Find function doesnt see the newly created file,
> and thus i cant delete & rename. My code looks something like this:
>
> Find.find(startingDir) do |path|
>   if File.directory?(path)
>         next
>   else
>         system("myapp #{path}")
>         puts path
>         if File.basename(path) =~ /^Mod-/
>           if File.exists?(path.sub('Mod-', ''))
>                 File.delete(path.sub('Mod-', ''))
>           end
>         File.rename(path, path.sub('Mod-', ''))
>         end
>   end
> end
>
> I was wondering if there was a way to reset the path one level up
> (i.e. where "puts path" is above), that way the current directory
> would be refreshed, and the new files would be recognized.

I don't think so. You'll probably have to use Dir.glob, keep a
separate array of paths already visited and manually rewind back to
your queue.

You post does give me some devilish ideas for my file-find library,
and made me reconsider the implementation in general. I think I should
use Dir.new (instead of Dir.foreach) and iterate over the file list
using the returned handle. That way I can use Dir#rewind, and "fast
forward" to a given point in an array of already visited paths. You
may want to consider that approach as well.

I'll also post what I come up with for file-find. :)

Regards,

Dan