Clever Geek Handbook

How to find characters not in parentheses

Trying to find all occurrences of characters

string1 = '%(example_1).40s-%(example-2)_-%(example3)s_'

so the output has all occurrences of '-' '_' not in parentheses

['-', '_', '-', '_']

No need to care about nested parentheses

+3


source to share


2 answers


Below is your output:

>>> import re
>>> str = '%(example_1).40s-%(example-2)_-%(example3)s_'
>>> print list("".join(re.findall("[-_]+(?![^(]*\))", str)))
['-', '_', '-', '_']


What this means is, it finds all substrings containing '-'

and / or '_'

in str

, not in parentheses. Since these are substrings, we get all such matching characters by concatenating and parsing into a list.

+2


source


You can use a module re

to do this by passing a regular expression to it

import re

str = '%(example_1).40s-%(example-2)_-%(example3)s_'
#remove all occurences of paratheses and what is inside
tmpStr = re.sub('\(([^\)]+)\)', '', str)

#take out other element except your caracters
tmpStr = re.sub('[^_-]', '', tmpStr)

#and transform it to list
result_list = list(tmpStr)

Result



['-', '_', '-', '_']

And as Bharath shetty mentioned in a comment, don't use str

, it is a reserved word in python for inline strings

+5


source






More articles:


All Articles