From: Robert Klemme <shortcutter@...>
Date: 2010-09-20T16:25:56+09:00
Subject: Re: Ruby regexpresion, error? :-(

On Sat, Sep 18, 2010 at 8:41 PM, Brian Candler <b.candler@pobox.com> wrote:
> iMelody Ooo wrote:
>> Dear Brian Candler, thank you very much, but still have problem.
>>
>> I read a line from file,want to macth ";"
>>
>> f = File.open(filename)
>> f.each do|line|
>>   puts line
>>   puts line.match( %r{;$})
>>   puts line.match( %r{;\z})
>>   puts line.match( %r{(.*);$})
>>   puts line.match( %r{(.*);\Z})
>> end
>>
>> result:
>> ABC DEF="";
>> nil
>> nil
>> nil
>> nil
>
> Change
>  puts line
> to
>  puts line.inspect
>
> Then you'll see that the line you've read is probably
>
> "ABC DEF=\"\";\n"
>
> (i.e. there's a newline at the end. \" is how inspect shows a
> double-quote within a double-quoted string)
>
> I would have expected %r{(.*);$} to match though:
>
>>> line = "ABC DEF=\"\";\n"
> => "ABC DEF=\"\";\n"
>>> line =~ %r{(.*);$}
> => 0

OP, I suggest you do this and post the outcome - then we can see what
goes wrong:

RXS = [
  %r{;$},
  %r{;\z},
  %r{(.*);$},
  %r{(.*);\Z},
]

File.foreach filename do |line|
  p line
  RXS.each {|r| printf "  rx=%p match=%p\n", r, r.match(line)}
end

Kind regards

robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/