Regex Matching - Python

Question

I need to write a regex matching pattern code to either return true if there is one '+' between two words and nothing else. I have written the code to check if there is only one '+' in the string but how will I check it is between two words? The code is below:

import re

inputStr= "ali+ahmedafaw+"
inputStr2= "hello+world+again"

plus=re.findall(r'[+]', inputStr)

print (plus)

l_plus=len(plus)
print "The length is ",l_plus

if l_plus<=1:
    print "True"
else:
    print "False"

Possible duplicate of [Reference - What does this regex mean?](http://stackoverflow.com/questions/22937618/reference-what-does-this-regex-mean) — ivan_pozdeev, Mar 03 '16 at 20:32

score 1 · Answer 1 · answered Mar 03 '16 at 20:34

Actually it depends on what you mean by word. If you mean a word with more than one character, you can simply use [a-zA-Z]+ around the + character. Or other patterns which will match different characters like \w to match word characters.

re.search(r'[a-zA-Z]+\+[a-zA-Z]+', input_str)

But if you just want it doesn't appears at the leading and trailing of your text you can use negative look-around:

re.search(r'(?<!^)\+(?!$)', input_str)

Regex Matching - Python

1 Answers1