From: Marko Schulz <in6x059@...>
Date: 2001-12-23T06:48:45+09:00
Subject: [ruby-talk:29323] Re: upper case to lower

On Sat, Dec 22, 2001 at 05:20:02PM +0900, nobu.nokada@softhome.net wrote:
> 
> Thanks to explain.
> 
> At Sat, 22 Dec 2001 15:55:12 +0900,
> HarryO <harryo@zipworld.com.au> wrote:
> > >> Dir.entries(X).each do |f|
> > >>   (n = f.dup).downcase! and File.rename(File.join(X, f), File.join(X,
> > >>   n))
> > >> end
> > >>
> > > okey I don't understand the "!" part why do u have it
> > 
> > In Ruby, methods that modify an object, as opposed to returning
> > a new version of an object with the requested change, tend to
> > end with '!'.
> 
> And it uses the fact that String#downcase! returns nil if no
> change occurred, to rename only files which contain upper
> cases.

It is code like that, that is giving Perl a bad reputation. It works,
but it does not communicate what it does. 

IMNSHO the code posted by Joseph McDonald is much better (after
replacing the String#tr with String#downcase).

I wish this wouldn't be(come) custom in Rubyland.

-- 
marko schulz