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Python Regular Expressions in Python Introduction to Regular Expressions Word Length

Posted by Tan Yang
Tan Yang
13,163 Points

regext: r"\w{count,}"

I set regex r"\w{count}", count is an integer variable, but it does't return correct result. How can I pass a variable to regex format

word_length.py 
import re

# EXAMPLE:
# >>> find_words(4, "dog, cat, baby, balloon, me")
# ['baby', 'balloon']

def find_words(count, string):
    lst = re.findall(r"\w{count,}", string)
    return lst

1 Answer

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

Python won't interpolate in a raw "r" string, for that you need an "f" string. But then you'll also need to put braces around the variable name and double the braces that you want to keep (as braces):

    lst = re.findall(f"\w{{{count},}}", string)