From: Chris Gernon <kabigon@...>
Date: 2006-11-03T07:18:20+09:00
Subject: Re: str1 = str2 is not a copy?!?

Joe Ruby MUDCRAP-CE wrote:
> WHY is var line getting changed by operations on var base_name? Isn't 
> 'base_name = line' supposed to create a copy? '=' in this case seems to 
> be acting like an alias or something.

Yep. All variables in Ruby are actually references to objects ... so 
using the = operator actually signifies "this variable now points at the 
same object as that variable". What you want is probably either:

base_name = line.clone

or

base_name = String.new(line)

but it would probably make more sense to just create base_name at the 
first operation where you want the two to be different - for example:

  line.strip!
  puts line

  base_name = line.sub('www.', '')
  base_name.sub!(/\.\w+$/, '')

  puts line

> BTW, is there a foreach function that automatically strips off the 
> newlines from line? Returning the record separators is silly.

Hmmm, not that I know of. However, I just want to mention that you 
probably want String#chomp rather than String#strip, unless you actually 
want to strip whitespace from the beginning of the string as well.

> Currently hating Ruby,
> Joe

Watch it - you may be in danger of losing your MUDCRAP certification ... 
;)

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