regular expression

[Sean 'Shaleh' Perry]

On 18-May-2002 Batara Kesuma wrote:
> Hi Sean,
> 
> On Sat, 18 May 2002 10:46:19 -0700 (PDT)
> "Sean 'Shaleh' Perry" <shalehperry at attbi.com> wrote:
> 
>> you are very close to what you need.
>> 
>> rule = re.compile(r'^\d{6}$') # ^ means start of string, then \d{6} is 6
>> numbers
>>                               # then $ is end of string.
> 
> Thank you very much. But what does the 'r' in (r'^\d{6}$') means?
> 

r'' is a 'raw' string, the contents of it generally do not need to be escaped. 
If you did not use the r'' syntax the above call would have been:

rule = re.compile('^\\d{6}6') # note the escaped backslash.

If you have a more complex regex all of the escaping makes it hard to read.

rule = re.compile('^\\d{6}\\s+\\d{3}')