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Python Regular Expressions in Python Introduction to Regular Expressions Escapes

sarvienn thevendran
sarvienn thevendran
734 Points
Posted by sarvienn thevendran
sarvienn thevendran
734 Points

re.search : how is this supposed to work?

in this re.search function I dont know where i can place my raw source.. as in doesn't the re.search function need a place you want it to look at? i am getting an erroe saying it is missing a positional argument

escapes.py 
import re
def first_number(expr):
    return re.search(r'\d',expr)

def numbers(cnt,str):
    return re.search(r'\str' * cnt)

1 Answer

Jonathan Grieve
MOD
Jonathan Grieve
Treehouse Moderator 91,253 Points
Jonathan Grieve
Jonathan Grieve
Treehouse Moderator 91,253 Points

The numbers function isn't quite right. I think what you need to do there is cast the return value as a string, so you get the required number of numbers in your result.

So... the reference to re. is simply calling the regular expression library so you can use search and match methods.

You're right to try and multiply in your return. But you just need a simple regular expression and then reference your function arguments in your call to search.

So simply...

    return re.search(r'\d' * cnt, str)