Python keyword and or usage example, python keyword andor

Python keyword and or usage example, python keyword andor

The and Expression in python is calculated from left to right. If all values are true, the last value is returned. If false exists, the first value is returned.

Or is also a calculated expression from left to return the first true value.
Copy codeThe Code is as follows:
IDLE 1.2.4
>>> 'A' and 'B'
'B'
>>> ''And 'B'
''
>>> 'A' or 'B'
'A'
>>> ''Or 'B'
'B'

Usage similar to the three-object expression: bool? A: B
Copy codeThe Code is as follows:
>>> A = 'first'
>>> B = 'second'
>>> 1and a or B # is equivalent to bool = true.
'First'
>>> 0 and a or B # is equivalent to bool = false.
'Second'
>>> A =''
>>> When 1and a or B # a is false, an error occurs.
'Second'
>>> (1and [a] or [B]) [0] # Security usage, because [a] cannot be false, at least one element
''
>>>