regular expression

[Sean 'Shaleh' Perry]

On 18-May-2002 Batara Kesuma wrote:
> Hi,
> 
> I tried to look at the docs, but couldn't get it.
> 
> How can I compile the regex rule, and match a list? I want to print out
> only list that contains 6 digits in it.
> 
> --- start ---
> 
> import re
> list = ['123456', '234567', '123', 'abc', '1234567']
> 
> for x in list:
>   rule = re.compile(\d{6,6})  // here I don't know...
>   if rule.match(x):
>     print x
> 
> --- end ---
> 

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.
for x in list: # btw, naming a list 'list' is a bad idea
  if rule.match(x):
    print x

or

good = filter(rule.match, list)
for x in good:
  print x