backreference in regexp

2006-01-31 Thread Schüle Daniel 
X-Enigmail-Version: 0.76.5.0
X-Enigmail-Supports: pgp-inline, pgp-mime
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit

Hello @all,

  p = re.compile(r(\d+) = \1 + 0)
  p.search(123 = 123 + 0)

'search' returns None but I would expect it to
find 123 in group(1)

Am I using something that is not supported by Python
RegExp engine or what is the problem with my regexp?

Regards, Daniel

-- 
http://mail.python.org/mailman/listinfo/python-list

Re: backreference in regexp

2006-01-31 Thread Fredrik Lundh 
Schüle Daniel wrote:

 Hello @all,

  p = re.compile(r(\d+) = \1 + 0)
  p.search(123 = 123 + 0)

 'search' returns None but I would expect it to
 find 123 in group(1)

 Am I using something that is not supported by Python
 RegExp engine or what is the problem with my regexp?

plus matches one or more instances of the previous item.  to make
it match a plug sign, you have to escape it:

p = re.compile(r(\d+) = \1 \+ 0)

/F



-- 
http://mail.python.org/mailman/listinfo/python-list

Re: backreference in regexp

2006-01-31 Thread Schüle Daniel 
thank you, I completely forgot that + is one of metacharacters

Regards, Daniel

-- 
http://mail.python.org/mailman/listinfo/python-list