Question

I am getting a different output in python 2 and 3 when I execute same code for regular expression.

Suppose this is the data that I want which is located somewhere in the webpage.

source = ['\x1e\x1e5.5.30-log\x1epcofiowa@localhost\x1epcofiowa_pci\x1e',
          '\x1e\x1e5.5.30-log\x1epcofiowa@localhost\x1epcofiowa_pci\x1e', 
          '\x1e\x1e5.5.30-log\x1epcofiowa@localhost\x1epcofiowa_pci\x1e', 
          '\x1e\x1e5.5.30-log\x1epcofiowa@localhost\x1epcofiowa_pci\x1e']

So, when I run the below code in python 2.6, it works perfect. I’m getting exact output like above.

match = re.findall("\x1e\x1e\S+",source)

But when I execute it in python 3.3 like:

match = re.findall("\x1e\x1e\S+", str(source))

I’m getting the output of the match variable like:

['\x1e\x1e5.5.30-log', '\x1e\x1e5.5.30-log', '\x1e\x1e5.5.30-log','\x1e\x1e5.5.30-log']

So, would you please tell me that why it’s not taking whole string in python 3? Why it’s skipping \x1epcofiowa@localhost\x1epcofiowa_pci\x1e each time? I want output like python 2.6.

So, I am clueless at this moment. I’m waiting for your reply. Thanks.

Answer 1

Seems like \S behave differently in Python 2 and Python 3.

According to Python 3 re module docs: –

\S – Matches any character which is not a Unicode whitespace
character. This is the opposite of \s. If the ASCII flag is used this
becomes the equivalent of [^ \t\n\r\f\v] (but the flag affects the
entire regular expression, so in such cases using an explicit [^
\t\n\r\f\v] may be a better choice).

Now, since \x1e (equivalent to U+001E, that comes after your \x1e\x1e5.5.30-log is a unicode whitespace character – reference to activestate, so it is not matched by \S in Python 3.

---

Whereas in Python 2: –

\S – Matches any non-whitespace character; this is equivalent to the
class [^ \t\n\r\f\v].

So, it only considers the ASCII character set for matching non-whitespace, and hence it matches \x1e.