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regex negation help?
Why does print(re.findall(r'[\w]+[^hey]+', 'hey1234')) return 'hey1234' when I have included [^hey] to ignore the 'hey'? I thought it would return '1234'.
I understand that 'print(re.findall(r'[\w]+[^hey]+', 'hey1234'))' means match 1 or more occurrences of any number, letter, underscore that doesn't include 1 or more occurences of the letters h,e,y.
I know print(re.findall(r'[^hey]+','hey1234')) will return 1234 but why doesn't print(re.findall(r'[\w]+[^hey]+', 'hey1234'))?
Chris FreemanTreehouse Moderator 68,404 Points
Good question! The [\w]+[^hey]+ says 1 or more alphanumeric character followed by 1 or more characters that are not “h”, “e”, or “y”.
- The first part [\w]+ matches “hey123” as they’re all alphanumeric characters
- The second part [^hey]+ matches “4” since it is not “h”, “e”, or “y”.
If you drop the first + to make the first part [\w], then the pattern would return “y1234” since “y” is the first alphanumeric character that isn’t followed by “h”, “e”, or “y”.
Post back if you need more help. Good luck!!!