9.13. The in and not in operators¶
The in operator tests if one string is a substring of another:
1
print('p' in 'apple')2
print('i' in 'apple')3
print('ap' in 'apple')4
print('pa' in 'apple')5
(chp8_in1)
Note that a string is a substring of itself, and the empty string is a substring of any other string. (Also note that computer scientists like to think about these edge cases quite carefully!)
5
1
print('a' in 'a')2
print('apple' in 'apple')3
print('' in 'a')4
print('' in 'apple')5
(chp8_in2)
The not in operator returns the logical opposite result of in.
2
1
print('x' not in 'apple')2
(chp8_in3)