Regular Expressions

[Ron]

This is probably a repeated question, but try as I might I was unable
to find something similar in the archives.

I'm trying to develop a regular expression for recognizing a simplified
C-Style string syntax. I need it to be able to handle escape sequences
of the form \x where x is any character including ".

Here's what I'm trying:

\"([^"\\]|(\\.))*\"

When I try to get it to recognize something like:

"I said, \"Hello!\""

It stops at the first quote after the \.

I've used this very same regular expression in a parser generator I
have for C++ and it works just fine.

Any thoughts on what I'm doing wrong in the Python Reg Ex world?

Thanks for the comments & help.

Ron

[MyHaz]

Re: Regular Expressions

escape chars are always a pain when making regex's. There is a section
on it the Regex HOWTO

http://www.amk.ca/python/howto/regex/regex.html#SECTION000420000000000000000

[Roel Schroeven]

Re: Regular Expressions

Ron wrote:[color=blue]
> This is probably a repeated question, but try as I might I was unable
> to find something similar in the archives.
>
> I'm trying to develop a regular expression for recognizing a simplified
> C-Style string syntax. I need it to be able to handle escape sequences
> of the form \x where x is any character including ".
>
> Here's what I'm trying:
>
> \"([^"\\]|(\\.))*\"
>
> When I try to get it to recognize something like:
>
> "I said, \"Hello!\""
>
> It stops at the first quote after the \.[/color]

Works for me:
[color=blue][color=green][color=darkred]
>>> print re.search(r'\"([^"\\]|(\\.))*\"',[/color][/color][/color]
.... r'"I said \"Hello!\""').g roup(0)
"I said \"Hello!\""


You can leave out the backslashes in fron of the first and last quotes
in the regex, by the way, at least if you use ' instead of " to delimite it:
[color=blue][color=green][color=darkred]
>>> print re.search(r'"([^"\\]|(\\.))*"',[/color][/color][/color]
.... r'"I said \"Hello!\""').g roup(0)
"I said \"Hello!\""


--
If I have been able to see further, it was only because I stood
on the shoulders of giants. -- Isaac Newton

Roel Schroeven