How to decipher :re.split(r"(\(\([^)]+\)\))" in the example
cs at zip.com.au
Fri Jul 11 03:29:34 CEST 2014
On 10Jul2014 08:37, fl <rxjwg98 at gmail.com> wrote:
>This example is from the link:
>I have thought about it quite a while without a clue yet.
>I notice that it uses
>double quote ", in contrast to ' which I see more often until now.
With raw strings (r', r") this doesn't matter. I tend to use r' myself.
You want raw strings with regular expressions because otherwise their heavy use
of sloshes "\" overlap with Python's use of sloshes, making everything harder.
>It looks very complicated to me. Could you simplified it to a simple example?
>split_up = re.split(r"(\(\([^)]+\)\))",
> "This is a ((test)) of the ((emergency broadcasting station.))")
>["This is a ", "((test))", " of the ", "((emergency broadcasting station.))" ]
Rip off the python punctuation and get the regexp itself:
then start from the inside out:
[^)] Any character except a closing bracket.
+ One or more of the preceeding.
[^)]+ One or more characters which are not closing brackets.
Also phrased: at least one character which is not a closing bracket.
Outside this are \( and \): these are literal opening and closing bracket
Two opening brackets, then at least one character which is not a
closing bracket, then two closing brackets.
The outermost ( and ) are regexp grouping brackets, not text. On their own you
don't need them, but they mark out the regexp between them for later reference
or for use with a repeating modifier like ?, * or +. So in this instance they
do not add anything special to the regexp.
Given the above inside-to-out explaination, does that explain the re.split
result for you?
Cameron Simpson <cs at zip.com.au>
I thought the DoD was a bunch of licensed squids. The last thing you
need is a bunch of unregulated, amateur squids running loose.
- David Wood <davewood at teleport.com>
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