Hi Navaneethan, It is like riding a bicycle; initially you falter a bit but later you ride with style.
See http://www.regular-expressions.info/tutorial.html and http://www.regular-expressions.info/javascript.html Try not to build too complex expressions; always think of the guy who has to maintain it long after you have coded it. Run /Python26/Tools/Scripts/redemo.py to interactively test your regular expressions. It works really well. If you want to use and see named groups you can update redemo.py with: Between line 150 and 151: self.grouplist.insert(END, g) nmatches = nmatches + 1 Insert (de-dented once, same as for line 148): #_________________________________________Start Chris Matthews 10 May 2005 self.grouplist.insert(END, "Named Groups:") GroupDict = m.groupdict() if GroupDict: self.grouplist.insert(END, "{") keysGroupDict = GroupDict.keys() keysGroupDict.sort() for Name in keysGroupDict: self.grouplist.insert(END, "'%s': '%s'" % (Name, GroupDict[Name])) self.grouplist.insert(END, "}") lstFindAll = self.compiled.findall(text) self.grouplist.insert(END, "\nFindAll: %s" % (lstFindAll)) Here is a nice quick reference to print and keep close by: ================================================================================================================= Regular Expression Primitive Quick Reference Regular expressions can contain both special and ordinary characters. Most ordinary characters, like "A", "a", or "0", are the simplest regular expressions; they simply match themselves. You can concatenate ordinary characters, so last matches the string 'last'. Some characters, like "|" or "(", are special. Special characters either stand for classes of ordinary characters, or affect how the regular expressions around them are interpreted. The special characters are: . (Dot.) In the default mode, this matches any character except a newline. ^ (Caret.) Matches the start of the string. $ Matches the end of the string. * Match 0 or more repetitions of the preceding RE. + Match 1 or more repetitions of the preceding RE. ? Match 0 or 1 repetitions of the preceding RE. {m} Specifies that exactly m copies of the previous RE should be matched. {m,n} Causes the resulting RE to match from m to n repetitions of the preceding RE. \ Escapes special characters ("*", "?", or \a \b \f \n \r \t \v \x \\) [] Range of characters e.g. [0-3A-C] for 0123ABC, [^5] match any except "5". | Or () Group (?P<name>...) Named group Regular Expression Extended Quick Reference \d Any decimal digit; same as [0-9]. \D Any non-digit character; same as [^0-9]. \s Any whitespace character; same as [ \t\n\r\f\v]. \S Any non-whitespace character; same as [^ \t\n\r\f\v]. \w Any alphanumeric character and the underscore; same as [a-zA-Z0-9_]. \W Any non-alphanumeric character; same as [^a-zA-Z0-9_]. ================================================================================================================= -----Original Message----- From: django-users@googlegroups.com [mailto:django-users@googlegroups.com] On Behalf Of Kenneth Gonsalves Sent: 11 February 2011 08:50 To: django-users@googlegroups.com Subject: Re: Need a tutorial for 'regexpr' On Thu, 2011-02-10 at 22:47 -0800, NavaTux wrote: > Do you know any elegant tutorial to learn a regular > expression from a nutshell ? i have referred some links which are > given in > a syntax without simple example, just i need a simple examples with > clear > explanation even i tried in past two days to pick it http://www.python.org/doc//current/howto/regex.html -- regards KG http://lawgon.livejournal.com Coimbatore LUG rox http://ilugcbe.techstud.org/ -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com. To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en. -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com. To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
