Logical Operators on String in Python

For strings in python, boolean operators (and , or, not) work. Let us consider the two strings namely str1 and str2 and try boolean operators on them:

str1 = '' 
str2 = 'geeks'
  
# repr is used to print the string along with the quotes 
  
print(repr(str1 and str2))      # Returns str1  
print(repr(str2 and str1))      # Returns str1 
print(repr(str1 or str2))       # Returns str2  
print(repr(str2 or str1))       # Returns str2 
  
str1 = 'for'
  
print(repr(str1 and str2))      # Returns str2  
print(repr(str2 and str1))      # Returns str1 
print(repr(str1 or str2))       # Returns str1  
print(repr(str2 or str1))       # Returns str2 
  
str1='geeks'
  
print(repr(not str1))          # Returns False 
  
str1 = ''  
  
print(repr(not str1))          # Returns True  
  
# Coded by Nikhil Kumar Singh(nickzuck_007)

Output:

''
''
'geeks'
'geeks'
'geeks'
'for'
'for'
'geeks'
False
True

The output of the boolean operations between the strings depends on following things:

Python considers empty strings as having boolean value of ‘false’ and non-empty string as having boolean value of ‘true’.
For ‘and’ operator if left value is true, then right value is checked and returned. If left value is false, then it is returned
For ‘or’ operator if left value is true, then it is returned, otherwise if left value is false, then right value is returned.

Note that the bitwise operators (| , &) don’t work for strings.

This article is contributed by Nikhil Kumar Singh.

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