How to put a variable into the {} with re

Question

So if I have {count} my code does not work... but if I take it into another interpreter I can see it does work when I have a value e.g.  {4}
How come I pass the count variable into this {}  ?
```word_length.py
import re
EXAMPLE:
>>> find_words(4, "dog, cat, baby, balloon, me")
['baby', 'balloon']
def findwords(mycount, mystring):
  return re.findall(r'\w{mycount}', my_string) 
```

Michael Vandenburg · Accepted Answer

There's a more concise and consequently more opaque alternative to .format that does work here:
return re.findall(r'\w{%d,}' % mycount, mystring) 
There's a manageable tutorial here (http://importflying.com/2011/conversational-programming-how-to-use-the-percent-sign-operator-in-python/). I didn't think the Python documentation (https://docs.python.org/2/library/stdtypes.html#string-formatting) was very clear on this one.

Chase Marchione · Answer

Hi David,
You'll want to explicitly convert my_count to a string, and place it outside of the quotes (when it's within quotes, the compiler interprets it as literal characters rather than a variable).
Python
return re.findall(r'\w{' + str(my_count) + ',}', my_string)

Hope this helps!

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David Hackett

David Hackett

How to put a variable into the {} with re

2 Answers

Michael Vandenburg

Michael Vandenburg

Chase Marchione

Chase Marchione

David Hackett

David Hackett

David Hackett

David Hackett