Removing element from a list by a regexp in Python

Question

I am trying to remove a string that is in parentheses from a list in Python without success.

See following code:

full = ['webb', 'ellis', '(sportswear)']
regex = re.compile(r'\b\(.*\)\b')
filtered = [i for i in full if not regex.search(i)]

Returns:

['webb', 'ellis', '(sportswear)']

Could somebody point out my mistake?

Answer 1

The \b word boundary makes it impossible to match ( at the beginning of a string since there is no word there (i.e. \b requires a letter, digit or underscore to be right before ( in your pattern, and that is not the case).

As you confirm you need to match values that are fully enclosed with (...), you need regex = re.compile(r'\(.*\)$') with re.match.

Use

import re
full = ['webb', 'ellis', '(sportswear)']
regex = re.compile(r'\(.*\)$')
filtered = [i for i in full if not regex.match(i)]
print(filtered)

See the IDEONE demo

The re.match will anchor the match at the start of the string, and the $ will anchor the match at the end of the string.

Note that if your string has newlines in it, use flags=re.DOTALL when compiling the regex (so that . could also match newline symbols, too).

Answer 2

>>> import re
>>> full = ['webb', 'ellis', '(sportswear)']
>>> x = filter(None, [re.sub(r".*\(.*\).*", r"", i) for i in full])
>>> x
['webb', 'ellis']

Answer 3

For my use case, this worked. Maybe it would be useful for someone finding the same problem

doc_list = dir(obj)
regex = re.compile(r'^__\w*__$')
filtered = [ele for ele in doc_list if not regex.match(ele)]