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 you wish to invoke a method if some boolean is true, you can put else None to terminate the trinary.

>>> a=1
>>> print(a) if a==1 else None
1
>>> print(a) if a==2 else None
>>> a=2
>>> print(a) if a==2 else None
2
>>> print(a) if a==1 else None
>>>

Answer 2

For the future time traveler from google, here is a new way (available from python 3.8 onward):

b = 1
if a := b:
    # this section is only reached if b is not 0 or false.
    # Also, a is set to b
    print(a, b)

Answer 3

You can definitely use num1 = (20 if someBoolValue else num1) if you want.

Answer 4

Another way num1 = (20*boolVar)+(num1*(not boolVar))

Answer 5

Use this:

num1 = 20 if someBoolValue else num1

Answer 6

num1 = 20 * someBoolValue or num1