Question

In Python, there are several values that count as False:

>>> if False or None or 0 or 0.0 or '' or [] or {} or set():
...   print 'True :)'
... else:
...   print 'False :('
... 
False :(

So, somewhere in my code I’m doing something like this:

    some_var = other_var or 'default' # Some default value

other_var could be None or any other value, if it’s None, some_var should be filled with 'default'.

But I kept having some troubles with this, so, debugging my code I found out that other_var sometimes was 0 (or any other value that counts as False), and some_var was filled with 'default' instead of 0.

So, is there a way to accomplish what I’m trying rather than doing this?

if other_var is None:
    some_var = 'default'
else:
    some_var = other_var

No is a valid answer.

Answer 1

There is the Conditional Expression (aka the “ternary operator”) syntax:

some_var = 'default' if other_var is None else other_var

Happy coding.