One line if-condition-assignment

Question

I have the following code

num1 = 10
someBoolValue = True

I need to set the value of num1 to 20 if someBoolV

Answer 1

If one line code is definitely going to happen for you, Python 3.8 introduces assignment expressions affectionately known as “the walrus operator”.

:=

someBoolValue and (num := 20)

The 20 will be assigned to num if the first boolean expression is True. The assignment must be inside parentheses here otherwise you will get a syntax error.

num = 10
someBoolValue = True

someBoolValue and (num := 20)
print(num) # 20

num = 10
someBoolValue = False

someBoolValue and (num := 20)
print(num) # 10