From: Mark Hubbart <discord@...>
Date: 2004-04-09T10:26:43+09:00
Subject: Re: need help with recursion


On Apr 8, 2004, at 5:54 PM, Boris "BXS" Schulz wrote:

> Hi,
>
> I was just trying to replace the underscores I get when using files 
> from my Linux-friends, but somehow my code seems to be corrupt.
> The code runs fine without the recursion, so it must be something 
> wrong in those three lines, but I do not know what :-(
> The "under_score.txt" is my testobject.
> I am using: Ruby 1.8.0, Windows XP
> Any help would be great.
>
> greetings, BXS
>
>
> This is my code:
>
> class FileHandling
> 	def noRecursiveUnderscore(basedirectory)
> 		Dir::foreach(basedirectory){ |filename|
> 		if File.stat(filename).file?
> 			newname = filename.gsub("_", " ")
> 			File.rename(filename, newname)
> 		end
> 		if File.stat(filename).directory? and filename != "." and filename 
> != ".."
> 			noRecursiveUnderscore(filename)
> 		end
> 		}
> 	end
>
> end #class
>
> testDir = FileHandling.new()
> testDir.noRecursiveUnderscore(Dir.getwd)
>
>
> **** This is my errormessage ****
> recursivenounderscore.rb:4:in `stat': No such file or directory - 
> under_score.txt
>   (Errno::ENOENT)
> [...]

You are correct, the problem *is* in the recursion part; you are 
stat()ing the same filename "with_underscores", but you had already 
renamed the file, so it gave an error. To fix it, make it an 
if..elsif..end, rather than two if..end's:

		if File.stat(filename).file?
			newname = filename.gsub("_", " ")
			File.rename(filename, newname)
		elsif File.stat(filename).directory? and filename != "." and filename 
!= ".."
			noRecursiveUnderscore(filename)
		end

That should fix that particular problem.

--Mark