Python - Extract pattern from string using RegEx

Question

I have a string in variable a as below:

a = 'foo(123456) together with foo(2468)'

I would like to use "re" to extract both foo(123456) and foo(2468) from the string.

I have two questions:

1. What is the correct regex to be used? foo(.\*) doesn't seem to work, as it treats 123456) together with foo(2468 as .*
2. How to extract both foo?

Answer 1

import re
pattern = re.compile(r'foo\(.*?\)')
test_str = 'foo(123456) together with foo(2468)'

for match in re.findall(pattern, test_str):
    print(match)

Two things:

1. .*? is the lazy quantifier. It behaves the same as the greedy quantifier (.*), except it tries to match the least amount of characters possible going from left-to-right across the string. Note that if you want to match at least one character between the parentheses, you'll want to use .+?.

2. Use \( and \) instead of ( and ) because parentheses are normally used inside regular expressions to indicate capture groups, so if you want to match parentheses literally, you have to use the escape character before them, which is backslash.