Regex Question

[Vlastimil Brom]

2012/8/18 Frank Koshti <frank.koshti at gmail.com>:
> Hey Steven,
>
> Thank you for the detailed (and well-written) tutorial on this very
> issue. I actually learned a few things! Though, I still have
> unresolved questions.
>
> The reason I don't want to use an XML parser is because the tokens are
> not always placed in HTML, and even in HTML, they may appear in
> strange places, such as <h1 $foo(x=3)>Hello</h1>. My specific issue is
> I need to match, process and replace $foo(x=3), knowing that (x=3) is
> optional, and the token might appear simply as $foo.
>
> To do this, I decided to use:
>
> re.compile('\$\w*\(?.*?\)').findall(mystring)
>
> the issue with this is it doesn't match $foo by itself, and requires
> there to be () at the end.
>
> Thanks,
> Frank
> --
> http://mail.python.org/mailman/listinfo/python-list

Hi,
Although I don't quite get the pattern you are using (with respect to
the specified task), you most likely need raw string syntax for the
pattern, e.g.: r"...", instead of "...", or you have to double all
backslashes (which should be escaped), i.e. \\w etc.

I am likely misunderstanding the specification, as the following:
>>> re.sub(r"\$foo\(x=3\)", "bar", "<h1 $foo(x=3)>Hello</h1>")
'<h1 bar>Hello</h1>'
>>>
is probably not the desired output.

For some kind of "processing" the matched text, you can use the
replace function instead of the replace pattern in re.sub too.
see
http://docs.python.org/library/re.html#re.sub

hth,
  vbr