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Flore W4,731 Points
Negation Regex I need help with \b
Here is a reminder of Kenneth's code:
import re names_file = open('names.txt', encoding = 'utf-8') data = names_file.read() names_file.close() print(re.findall(r''' \b@[-\w\d.]* [^gov\t]+ \b ''', data, re.X|re.I))
This gives a result of the @ part of email addresses, excluding "gov", a few examples here:
['@teamtreehouse.com', '@camelot.co.uk', '@spain.']
I have tried taking out the two '\b' and it gives the result:
['@kennethlove\nMcFarland, ', '@potus44\nChalkey, Andrew']
I don't understand why taking out the \b will mean that I find combinations including '\n', ',' and ' ' - none of those are contained in my @[-\w.+]*, so why would those appear?
Saikat Chowdhury3,116 Points
Hi Flore, /b is looking for word boundary or edges of the word define by white spaces. Here It will check start and end of the string.
my thinking is , when you remove two \b from your regex script then it started searching twitter records. And Twitter record has @ . Because of + sign it goes to next line . And you are getting below result eg. ['@kennethlove\nMcFarland, ', '@potus44\nChalkey, Andrew']
if you remove + sign from [^gov\t]\b then it will stay on same line, even you remove \b from your regex script.